Don Crisóstomo Ibarra is a young man of Filipino and Spanish descent who returns to the Philippines after a seven-year trip to Europe. Educated and idealistic, he seeks to implement progressive reforms in his hometown of San Diego, starting with the construction of a new school. His progressive views and widespread popularity make him a target for conservative colonial and religious figures who view his ideas as a direct threat to their authority.

Elías is a mysterious boatman and fellow Filipino who befriends Ibarra. Coming from a marginalized background haunted by generational oppression, his worldview leans toward radical ideology and immediate reform. Despite their class differences and contrasting political views regarding gradual change versus active uprising, he protects Ibarra and seeks his influence to advocate for the common people.

Father Dámaso is a conservative Franciscan friar who has lived in the Philippines for two decades. Quick to anger and prone to vice, he uses fear and intimidation to protect the church's established power in the region. He fiercely opposes Ibarra's progressive ideals, viewing the young man's European education as a direct challenge to the traditional colonial hierarchy.

Father Salví is the sickly and manipulative head sexton of San Diego. Unlike the physically imposing Father Dámaso, he schemes in the shadows and uses psychological manipulation to further his agenda. He harbors an intense obsession with María-Clara and views Ibarra with immense jealousy and contempt.

María-Clara is the sheltered fiancée of Don Crisóstomo Ibarra and the daughter of Captain Don Santiago. Widely admired and frequently compared to the Virgin Mary by the townspeople, she finds herself caught in the crossfire of the town's political and religious power struggles. Her loyalty to Ibarra is constantly tested by the interfering authorities around her.

Tasio is an elderly philosopher in San Diego who is considered a madman by most of the town's conservative citizens. He operates with a strictly rational and logical perspective, positioning himself outside traditional societal expectations. Progressive thinkers often seek his counsel, though he realistically warns them about the dangers of challenging the colonial power structure.

Captain Don Santiago, often called Tiago, is a wealthy resident and landowner in Manila. He maintains his fortune and societal standing by bribing friars and remaining rigidly traditional, effectively closing his doors to new progressive ideas. He profits from questionable enterprises like the opium trade and cockfighting while maintaining a facade of extreme piety.

Sisa is a loving but impoverished mother trapped in a cycle of poverty. She pushes her sons to work as sextons for the church in hopes of securing them a better life, while enduring neglect and exploitation from her gambling husband. Her existence is defined by daily hardship and a desperate devotion to her children.

Basilio is the ten-year-old son of Sisa who works as a sexton at the local church. Forced into difficult labor to support his impoverished family, he endures harsh treatment from the clergy. Despite his circumstances, he dreams of a grander future away from the abuses of San Diego.

Crispin is Sisa's seven-year-old son and a young sexton at the church. He is falsely accused of stealing by the head sexton, leading to severe punishments that expose the cruelty the religious order inflicts on the vulnerable lower class.

The ensign is the military leader of the civil guard in San Diego and a heavy drinker. He constantly battles the religious orders for dominance in the village and oversees a brutal police force that frequently abuses the local population. His home life is equally chaotic due to a toxic marriage.

Doña Consolación is the spiteful and envious wife of the ensign. Uncomfortable with her ill-defined place in San Diego's social hierarchy, she frequently lashes out at those less fortunate than herself. She engages in abusive behavior toward commoners and violent physical fights with her husband.

Don Filipo is the deputy mayor of San Diego and a leader of the town's liberal party. He occasionally tries to push back against the conservative faction and the friars, relying on strategies suggested by his politically savvy friends, though he struggles against entrenched local corruption.

The Captain General is the King's representative in the Philippines. Unlike the local friars, he possesses more progressive sensibilities and openly questions the barbarity of how the common people are treated by the authorities. He uses his high rank to counter the excessive punishments handed down by the church.

Victorina de Espadaña is a fiercely ambitious and status-obsessed woman who previously rejected local suitors to marry a Spaniard. Desperate to climb the social ladder, she forces her passive husband to pretend to be a medical professional and aggressively dictates the actions of those around her.

Tiburcio is the passive, common Spanish husband of Victorina de Espadaña. Driven by his wife's thirst for status, he masquerades as a doctor despite having no real medical expertise, prescribing dubious remedies like marshmallow syrup to his patients.

Linares is a young Spaniard introduced to San Diego society by Doña Victorina. He is maneuvered into becoming a replacement suitor for María-Clara after Ibarra is excommunicated, though he often seems uncomfortable with the aggressive social schemes surrounding him.

Señor Guevara is an old lieutenant of the civil guard who is one of the few individuals brave enough to publicly challenge the religious orders. He holds immense respect for the late Don Rafael and provides Ibarra with crucial information regarding his father's tragic fate in prison.

Don Rafael is the late father of Don Crisóstomo Ibarra and a highly respected, progressive citizen of San Diego. Prior to the events of the novel, he clashed with the church over religious practices and ultimately died in a prison cell after defending a Native child from an abusive tax collector.

Lucas is the brother of a foreman who was killed during the school's groundbreaking ceremony. He attempts to extract money from Ibarra before transitioning into a shadowy operative, manipulating vulnerable locals into participating in a violent, doomed uprising.

Bruno is a commoner whose father was brutally killed by the civil guard. Embittered by the injustice and impoverished by gambling, he becomes highly susceptible to recruitment into a planned subversive uprising against the local barracks.

Társilo is Bruno's brother, who also seeks revenge against the civil guard for the death of his father. His involvement in an underground uprising is driven purely by a desire for personal vengeance rather than grand political machinations.

Captain Pablo is the leader of a subversive group hiding in the wilderness. Disillusioned with the government and the church after suffering severe oppression, he plans a violent rebellion but is temporarily convinced by his allies to delay the attack in hopes of peaceful reform.

Teodora Viña is the wife of the deputy mayor, Don Filipo. She helps host the local liberal faction in their home and witnesses the political struggles her husband faces against the deeply entrenched conservative powers of San Diego.

Aunt Isabella is the relative and chaperone of María-Clara. She assists in managing the household alongside Captain Don Santiago and helps prepare her niece for important social and religious obligations, including confession.

Captain Basilio is a wealthy resident of San Diego who participates in the local vices heavily criticized by progressive thinkers. He represents the complacent upper class who prefer gambling and socializing over addressing the town's severe inequalities.

The mayor of San Diego is the official head of the local government but ultimately defers to the desires of the religious friars. His lack of backbone renders municipal meetings pointless and deeply frustrates his progressive deputy.

Father Sibyla is a Dominican friar who attends Captain Don Santiago's social gatherings. He represents the broader religious establishment that worries about losing its economic and social leverage over the Philippine population, believing that wealth rather than morality secures the church's influence.

Captain Martin is a minor character and resident of San Diego. He observes and documents the lavish, excessive spending that characterizes the town's religious festivals, highlighting the community's focus on superficial celebrations.

Sinang is a close friend and confidante of María-Clara. She provides a rare voice of honesty regarding María-Clara's true feelings, actively communicating with Ibarra about his fiancée's reluctance to marry the newly introduced Spanish suitor.

Captain Tinong is a former supporter of Ibarra who completely abandons the young man when political tides turn. Fearing that his past association will lead to his own arrest, he and his wife attempt to bribe colonial authorities to protect their social standing.