This study was conducted to examine the influence of family size and parental support on performance of secondary school students in financial accounting in Kaduna State, Nigeria. The study had four objectives, four research questions and four null hypotheses. The population of the study comprised of 3,128 and a sample size of 486 SS 2 students. Ex-post facto design was used for the study. Data was collected using a structured questionnaire and students' results were obtained from the school's examination offices. Percentages, mean and standard deviation were used to answer the research questions. Regression analysis was used to test null hypotheses 1 and 2 while t-test statistic was used to test null hypotheses 3 and 4 all at 0.05 level of significance. The study findings showed that family size and parental support significantly influenced the performance of secondary school students in Financial accounting in Kaduna state, Nigeria (0.05>0.000). On the basis of the findings, the researcher concluded that small family size and provision of learning materials by parents improved secondary school students' performance in Financial accounting in Kaduna state, Nigeria. It was recommended that students from large families should supported by teachers, private individuals and members of the community in order to improve their performance in Financial accounting. Parents should also support and give special attention to their children through organizing extra lessons and provision of learning materials.