The main function of this study was to determine the effect of school climate on students` academic achievement at secondary school level.The study was delimited to the five districts of the Punjab province of Pakistan.It was causal comparative as well as correlational. The Study which, was conducted on a sample of 1473 secondary schools students in the public schools of Punjab province.Data was collected through Student School Climate Questionnaire (SCSQ).The questionnaire had three major parts namely:Physical environment, social environment, and learning environment.The questionnaire contained 39 items at 5-point Likert scale.The validity and reliability of the questionnaire were ensured through the experts’ opinions and pilot testing. The overall reliability of the questionnaire was 0.90.The Study concluded positive correlation (r =.766) between School Climate and Students academic achievement.Also, the factors of school climate have a positive correlation with academic achievement of the students. The study further showed that school climate has positive effect on students’ academic achievement which measured through regression analysis.The findings of this study suggested that students achieve high achievement in schools with healthy climate.