The perceived influence of college club in increasing students' interest and achievement in Nigerian post-primary schools in Anambra State was studied using a survey research design. The population of the study comprised all senior secondary school science students in Anambra State totaling 9322 as at 2007. From this population, a sample of 140 senior secondary two (SS 11) science students was purposively drawn from those that participated at the Anambra State branch of Science Teachers Association of Nigeria (STAN) 2007 science quiz and exhibition competition. A 31-item validated researcher-developed questionnaire arranged in 3 clusters of 14, 10 & 7 was used to collect data. A reliability coefficient of 0.81 was established for the instrument using Cronbach-alpha. The result of the study revealed that senior secondary students in Anambra State testified that science clubs exist and is functional in most secondary schools in the state and has positive influence in increasing students' interest and achievement in science subjects as well as science and technology related careers. It was therefore recommended among others that every effort on the part of government, school head and students should be made to establish and sustain a functional science club in secondary schools in Anambra state.