The study aimed at establishing the sources of information about sexual reproductive health among school pupils in selected schools in Lusaka province. The objectives of the study were to: establish the prevalence of sex among pupils in secondary schools and to determine pupils’ sources of information about sexual health in selected secondary schools in Lusaka Province. A descriptive survey was used in conducting this research. The study used both qualitative and quantitative methods of data collection. The sample consisted 172 respondents: 88 girls and 84 boys drawn from six secondary schools in Lusaka province. In selecting the participants, simple random sampling technique was used. The study employed the questionnaire and focus group discussion to ensure validity of the findings. The quantitative data was analysed using the statistical package for social sciences computer software while the qualitative data was analysed by coding and grouping the emerging themes. The study has revealed that comprehensive sexuality education lessons were the main sources of information about sexual health of adolescents in secondary schools. 62% of pupils reported that they learnt about safe sex from CSE lessons at school. The study also has shown that more pupils in the age group of 20-21 years were involved in sex more than any other age groups. It also emerged from the study that 65% of pupils are in relationships and 65% had a protected sex. Arising from the findings of the study, the following recommendations were made: 1. The ministry of education should supply more books on sexuality education. The Ministry of Education should make CSE a stand-alone subject rather than integrating it in other subject.