This study analyzed factors associated with the quality of life (QoL) of prison officers (POs) in the Midwest Region of Brazil. POs in five penitentiary units participated in this cross-sectional study. Sociodemographic data were obtained through face to face interview and a World Health Organization Quality of Life abbreviated version (WHOQOL-BREF) questionnaire was applied to assess QoL. Student’s t-test or ANOVA were used for bivariate analysis and multiple linear regression was applied for adjusted analysis. The domains used for outcomes were: physical, psychological, social relations, and the environment. The lowest score among WHOQOL-BREF domains was environment (59.9; 95%CI 58.0–61.5). After adjustment, the factors associated with the physical domain were ‘female sex’ and ‘no history of workplace PO-PO violence’; factors associated with the psychological domain were ‘female sex’, ‘without spouse’, and ‘no history of inmate-PO violence’; factors associated with the social relationships domain were ‘female sex’, ‘work experience in years’, ‘no higher education’, ‘no private health insurance’, and ‘no history of inmate-PO violence’; and factors associated with environment domain were ‘female sex’, ‘work experience in years’, ‘no private health insurance’, and ‘no history of PO-PO violence’. This study showed that female workers and those with a history of violence at work had worse QoL scores. This investigation highlights the importance of prison management in promoting QoL of POs, as well as support and development of strategies to prevent workplace violence.