Dayanara 'Daya' Diaz is an inmate at Litchfield Penitentiary. She is portrayed by Dascha Polanco. Daya lived with her mother and four younger siblings, along with her mother's drug dealer boyfriend, Cesar. Daya served as the main caregiver of her brothers and sister while her mother ran around. After her mother took the fall for her boyfriend, Daya and her siblings visited her in prison, but their mother appeared to take no interest in them, and asked them why Cesar wasn't visiting. Daya later began a relationship with Cesar in retaliation against her mother. Daya arrived to prison for drug-related charges along with Piper. Upon arrival, Daya was slapped by her mother for being in prison. After experiencing problems with the other Latinas, she eventually strikes a relationship with CO, John Bennett.
Dayanara is quiet and laid back. She enjoys reading and drawing manga ever since she found a manga that was thrown in a trashcan when she was younger. She says the girls are more beautiful than Disney Princesses.