Importance Child abuse and neglect are associated with risk of negative health outcomes, and children in minoritiy racial and ethnic groups and female children are disproportionately affected. It is unclear whether the incidence of child maltreatment has changed over time. Objective To determine whether incidence of child maltreatment and its subtypes changed across sex, race, and ethnicity in the US from 2012 through 2023. Design, Settings, and Participants In this serial, population-based, cross-sectional study, all Child Protective Services cases in the US from January 2012 through December 2023 for children from birth to age 17 years were drawn from the National Child Abuse and Neglect Data System. Race and ethnicity were recorded as per the data system. Population estimates of US children for corresponding years were from the US Census Bureau. Main Outcomes and Measures Confirmed and referred cases of emotional abuse, physical abuse, sexual abuse, and neglect per 10 000 children by race, ethnicity, and sex. Results From 2012 through 2023, there were 7 326 987 confirmed cases (per 10 000 children: 87.51 female and 78.46 male; 79.52 American Indian and Alaska Native, 17.72 Asian, Native Hawaiian, Pacific Islander, 121.69 Black, 67.21 White, 91.22 of multiple races, and 75.72 Hispanic) and 32 980 613 referrals (per 10 000 children: 382.72 female and 361.35 male; 293.45 American Indian and Alaska Native, 88.81 Asian, Native Hawaiian, Pacific Islander, 550.54 Black, 294.80 White, 358.08 of multiple races, and 313.43 Hispanic) for child maltreatment. Overall, confirmed cases of all forms of maltreatment declined (average annual percent change [AAPC], −1.53; 95% CI, −2.07 to −1.05), except for sexual abuse, and remained unchanged for referrals (overall maltreatment AAPC, 0.11; 95% CI, −0.33 to 0.58). Decline in most confirmed subtypes of maltreatment was found for Asian, Native Hawaiian, and Other Pacific Islander (overall maltreatment AAPC, −1.77; 95% CI, −3.17 to −0.58), Hispanic (overall maltreatment AAPC, −1.81; 95% CI, −2.67 to −1.13), and White (overall maltreatment AAPC, −0.74; 95% CI, −1.08 to −0.42) children. Disparities persisted across the study period; incidence was lowest for all maltreatment subtypes among Asian, Native Hawaiian, and Other Pacific Islander children and generally highest among Black children. Both sexes experienced mostly decreases in confirmed cases and no changes in referrals for maltreatment overall (confirmed overall female maltreatment AAPC, −1.25; 95% CI, −1.64 to −0.90 and confirmed overall male maltreatment AAPC, −1.81, 95% CI, −2.53 to −1.21), but female children experienced more maltreatment, with disparities largest and widening over time for sexual abuse ( z score, 5.52; P &lt; .001). Conclusions and Relevance In this study, child maltreatment declined for confirmed cases and remain unchanged for referrals. Disparities persisted, particularly for Black children. This group with the most room for improvement experienced none, whereas that with least room for decline—Asian, Native Hawaiian, and Other Pacific Islander individuals—experienced improvements. Progress is needed in combating drivers of maltreatment, particularly poverty, and in targeting differential barriers to access to public health benefits programs.