High fertility is among the dominant demographic features of the developing countries including those in Sub - Saharan Africa despite measures to control it. The average Total Fertility Rate for the period between 1975 and 1980 was 7.0 and 5.5 between 2000 and 2007. Tanzania has high TFR although there are signs of fertility decline from 7.0 to 5.4 in the years 1970 and 2007 respectively. The main objective of the study is to determine the influence of socio-cultural factors on fertility. Specifically the study estimates the mean number of children ever born per woman, shows how sex preference affects fertility, shows how value of children affects fertility, associates fertility levels and status of women and shows linkage between fertility levels and religiosity. This cross sectional study uses quantitative data collected from a randomly selected sample of 110 women aged 15-49 years and four group discussions within the same age range. The key findings indicate that there is a positive relationship between socio-cultural determinants and fertility in Morogoro District. The TFR in the area of study is 6.1 which is higher than the regional and national fertility. The mean number of children ever born in the area of study is 8.0. Sex preference within the area of study is strongly related to fertility. Value of children has positive effects on number of children. Highly religion affiliated respondents have high number of children. Status of women has positive effects on number of children. Low status women have higher number of children. The study argues for family planning program for men and women. Men should be given explanations on advantages of discussing with their wives/partners on reproductive matters. To the women focused in this study, women should stand firm in decision making particularly on reproductive matters.