This study explored the relationship among self-esteem, peer pressure and the incidence of deviant behaviour among secondary school students in Delta State. A total of 2 research questions and 2 hypotheses guided the study. The correlational research design was adopted. The population comprised 72,854 senior secondary school students A sample size comprising of 1,045 students was selected through a multistage sampling procedure. Questionnaire (opinion poll) is the instrument was used for the study. The validity and reliability of the opinion poll was ascertained. The PPMCC of determination was used to answer the phrased research questions while regression was used to test the hypotheses at 0.05 level of significant. The answer of the study revealed that a major relationship exists between self-esteem (S.E) and deviant behaviour (DB) among secondary school students and that a significant relationship exists between peer pressure and deviant behaviour among secondary school students in Delta State. The researcher recommended that stake holders such as parents, educators and policy makers should do their part to ensure that the self-esteem of the adolescents be consciously enhanced to reduce deviant behaviour among secondary school students.