This study was conducted with the purpose of determining whether sonpreference exists in the study area as well as establishing the ideal family size among married women. These were correlated with contraceptive behaviour in order to establish their relationships. The study was conducted to a sample of 135 randomly selected married women aged between 15-49 years from Morogoro Municipality. Both a questionnaire and focus group interviews were used to collect the data. The results showed that mean ideal number of desired children was 4.2. When ideal family size was compared with contraceptive behavior results indicated the increase of current and intention to use contraceptive methods to women with more than two children. Majority of respondents did not show strong sex preference. When related with contraceptive use, current use of contraceptive use was found to be high among respondents with children of both sexes and low for respondents with children of single sex. Looking into actual sex composition, 47.3% had more boys than girls. When actual family size was related to contraceptive use, it was observed that majority were currently using contraceptive (67%), the same pattern was noted with the intention to use contraceptives, which was high - especially to those respondents with one or two children. The study recommends that, although the current use and intention to use contraceptives was high in the study area, more effort is needed to make sure that continuation rate is also high.Key words: Contraceptives, family size, sex preference, married wome