This study was designed to find out peer influence and parental support on the academic achievement of senior secondary school students in Giwa educational zone. The study used ex-post factor design. Cluster and simple random sampling were used to select the sample. Four senior secondary schools with a total population of 1606 and a sample size of 338 students were drawn and used for the study. Two questionnaires were used for the study, peer support i and of parental support inventories. The academic achievement was obtained from the scores in English language and mathematics from the students mock qualifying examination. Three hypotheses were formulated for this study and tested using Pearson Product Moment Correlation. The findings of the study show that there is a significant relationship between peer support and academic achievement (r=0.742, p=0.018), parental psychological support and academic achievement (r=0.756, p=0.003). A significant relationship also exist between parental monitoring for homework and academic achievement (r=0.838, p=0.002.) It is recommended that parents should offer psychological support to their children by way of communicating with their children about the value/utility of education, fostering educational and career aspiration in the child, linking of school work to current event, and making plans/preparations for the child‟s future. When students received such support they become more determined to achieve academically.