The main purpose of this study was to determine the effectiveness of social problem solving skills programme in the treatment of social cognitive deficiency among male secondary school students. The quasi-experimental equivalent control group design was adopted for this study. Three male schools in Sokoto metropolis were randomly selected, pre-tested, and assigned to two experimental conditions, namely: treatment and control groups. The treatment group was made up of two schools and had a sample size of 105 students, while the third school served as the control school and had a sub-total sample size of 64 students The treatment sessions were based on 12 treatment modules constructed for this study. These modules focused on particular topics considered necessary - in promoting social cognitive ability. For each of the two treatment schools, there were three contact periods per week and each contact or treatment session was centered on a particular treatment module. Treatment session mainly involved direct instructions, discussions and assignments and this researcher himself led all such sessions. In all, treatment lasted for four weeks. The "t" test for independent samples was used to test three of the null hypotheses for this study, while the fourth hypothesis was tested with the Mann-Whitney "u" test. Results of analyses on data collected led to the rejection of all four null hypotheses. Significant differences were found between the treatment and control groups in their post test mean scores on all research variables. The treatment group obtained significantly high post test mean scores on Social Information Processing Skill Scores (SIPSS) and Social Reasoning and Interpersonal Understanding (SRIU) factors, and lower posttest mean scores on attitudes and Personal Social psychological Problems Index (PSPPI). This means that treatment has yielded significant increases in participants' ability to solve social problems presented in hypothetical situations and to reason at higher levels in interpersonal dilemma situations compared to the control group. Although, the increases were assessed mainly on students' responses to hypothetical social and moral dilemma situations, discussions of the results seem to suggest that obtained results also have significant implications for participants' ability to solve real life personal, social and psychological problems. Increases or high scores on SIPSS and SRIU seem to point to better ability to solve personal, social and psychological problems, while low scores tend to indicate poor ability to solve such problems and hence greater susceptibility to real life personal, social and psychological problems. Several recommendations were also made based on the findings of the study. This include the need for intensive guidance and counseling based intervention programme to be mounted in male boarding schools within Sokoto Metropolis in order to remedy the relatively high prevalence of social cognitive deficiency. It was also recommended that more attention be paid to social and cultural factors, particularly, beliefs in superstitions, indiscriminate use of proverbs and manipulative interpretation of the belief in predestination because these seem to have negative influence on their social cognitive skills.