This study investigated the influence of social media on psychosocial behaviour and academic performance of secondary school students. It was conducted in Batagarawa Local Government, Katsina State, Nigeria. Two research hypotheses were formulated for the study, and descriptive survey research design was employed. The target population consists of four secondary schools purposively selected out of the seven public schools and 306 SSII students were randomly selected for the study. Researcher-made validated questionnaire and academic performance test in English Language was used for data collection. Collected data was analyzed using descriptive statistics of mean and standard deviation. Null hypotheses were subjected to t-test of independent samples. The study found among others that, social media usage has negative influence on psychosocial behaviour and academic performance. It therefore recommended that parents, teachers, and educational psychologists should pay more attention to their students' attitude on these platforms and also educate them on time management as not to waste too much of their time chatting, they should concentrate on their studies.