Crop diversification is an important issue in agriculture that has impact on both food security and farm incomes. The objective of this study was to assess the factors affecting crop diversification of smallholder farmers in Masaiti district. Data for the study were collected from a sample of 200 farmers selected using the clustered sampling method. A questionnaire administered by the researcher was used for data collection. Data were analysed using descriptive statistics and logistic regression. Crop diversification was estimated using the Simpson Diversification Index (SDI).The results of the logistic regression model revealed that, farming experience and age of the farmers significantly influence crop diversification. The other variable namely household size, gender, labour cost, household income, FISP, number of field plots had no significant effect on crop diversification.According to the findings of the study, age group, household size, extension contact, crop revenue, crop area group, FISP and monthly income had a positive influence towards crop diversification and crop production Education attainment, farming experience, and early supply of inputs have a negative impact on crop diversification and crop production. The research findings correlated with the reviewed literature and the research questions were answered. The mean crop diversification of 0.3650 showed that there was less diversification among the FISP beneficiaries and non-beneficiaries in Masaiti district.