This study was carried to investigate the influence of socio-cultural practice (male child preference; women marginalization and adoption of large family size) on fertility behaviour in Alayi community. Survey design was adopted for this study. Data collection was carried out using two methods (questionnaire and Focus Group Discussions-FGDs). The questionnaire consists of four sections, with twenty items arranged on four Point Likert-type formats. A pilot test of the instruments gave reliability estimates of 0.5. Using the proportional stratified and purposive sampling technique, 356 respondents were sampled from a population of 3,273 respondents across the study area. Three hypotheses were formulated and tested using chi-square at 0.05 level of significance. Results obtained indicated that there is a significant influence of male child preference, women marginalization and adoption of large family size on the fertility behaviour of Alayi people. Also, result from the socio demographic data of respondents indicates that the level of education and occupation of respondents has a far-reaching implication for large family size among the Alayi people. It is recommended among others that age of entry into marriage should be checkmated by parents and stakeholders to prevent women from falling victims of circumstances. Also, there should be an appeal for the shift in the traditional beliefs and attitudes in which people consider many children with preferences to sons and synonymous with wealth. Lastly, the existing family planning programme should be strengthened and expanded to ensure that couples and individuals have uninterrupted access to the range of contraceptive methods at affordable prices.