Abstract: Over the past five years, Girls performance in the Kenya Certificate of Primary Education (KCPE) Examination in primary schools in Navakholo Sub-County has been dismal. Poor KCPE performance hinders placement of girls in National Schools, quality extra County schools and by extension, admission for good professional careers. The purpose of this study was to assess the influence of socio cultural practices on girl child KCPE examination performance in primary schools in Navakholo Sub-County. This was a descriptive study that employed a mixed methods designs approach. Questionnaires were used to collect data from 360 standard eight girls recruited through Stratified Random sampling. Interview guides were used to collect data from 15 Key Informants and 6 Focus groups purposively selected. Quantitative data obtained was analysed using descriptive statistics with the aid of SPSS computer software program. Qualitative data was analysed by content analysis. The study established that stereotypic gender role dispositions are the major socio cultural factors that lead to girls’ poor performance in KCPE Examination. The study recommends that parents be encouraged to minimize domestic chores for girls, and that Policy decisions should focus on increase Free Primary Education Funds to so that schools’ can cater for girls needs as well to enhance girl child KCPE Examination performance.