The study aimed to identify the degree of prevalence of early active maladaptive cognitive schemas and depression disorder among the inmates of the central prison in Samail region in the Sultanate of Oman, and to verify the existence of differences in the averages of the degree of prevalence of early active maladaptive cognitive schemas and depression among the sample of adult prisoners in the central prison in Samail due to demographic variables (gender). , age, academic level, marital status), and revealing the nature of the correlation between the types of early active incompatible cognitive schemes and depression among the study sample. The study sample consisted of (1000) inmates of the central prison in Samail, divided into (505) males and (495) females, their ages ranged between (less than 29 years – more than 50 years). The study relied on the descriptive correlative approach, and the researcher used psychometric study tools: the "Jeffrey Young" scale of adaptive cognitive schemas, the abbreviated version (translated by: Muhammad Al-Sayyid Abd al- Rahman, and Muhammad Ahmad Saafat, 2014), and the "Aaron Beck" depression scale in its abbreviated form, which consists of (20) A set of symptoms (translation and codification: Gharib Abdel-Fattah, 1985). The results of the study showed: 1. The degree of prevalence of early, active, incompatible cognitive schemas came with a moderate degree of prevalence in all dimensions of the early incompatible cognitive schemas scale among the study sample. 2. The degree of prevalence of depression came in a medium degree in the average degrees of prevalence of depression among the study sample. 3. There are statistically significant differences at the level of significance (α = 0.05) in the estimates of the study sample responses about the degree of prevalence of early active incompatible cognitive schemes due to the variables (gender, age, and marital status) and were in favor of the male sample and the age ranged from (30 to 39). years), single and divorced, and there are no statistically significant differences due to the educational level variable. 4. There are statistically significant differences in the estimates of the study sample's responses about the degree of depression due to the variables (educational level and marital status) and were in favor of the bachelor's degree or less and the single and divorced marital status. Also, there were no statistically significant differences due to the variables gender and age. 5. There is a statistically significant positive and direct correlation between the early active incompatible cognitive schemas and depression among the sample of inmates of the central prison in Samail in the Sultanate of Oman. The researcher recommended working on providing counseling and treatment programs for those with a high degree of depression among prison inmates, based on cognitive schema therapy prepared by "Jeffrey Young".