More than 70 percent of Tanzanians live in rural areas and close to 90 percent of them practice agriculture. Kishapu and Mvomero Districts are highly food insecure, nutritionally vulnerable, lack nutritional interventions and differ in rain patterns, farming practices and economic activities. This study sets out to examine how market access influences the food security status of low-income farm households in rural Tanzania. Both qualitative and quantitative data were collected in 2014: quantitative data comprised structured questionnaires in two phases of household surveys (before and after harvest) and monthly market price surveys. Qualitative data comprised key informant interviews and focus group discussion. Coding, cleaning and analysis of quantitative data was done in SPSS while qualitative data was transcribed, coded and organised into themes. Mvomero exhibited significantly better household incomes, food security and market accessibility than Kishapu. Binomial regression was performed on household food security determining variables which were categorised into food secure and food insecure, variables in the models explained more than 60 percent of variations in the dependent variables. Results indicated statistical significance in the pre-harvest season such that households close to the market, owning bicycles, in higher income quartiles and with smaller household size were less likely to be food insecure than their counterparts. Post-harvest regressions showed no statistical significance except for the prevalence category of household food insecurity where market access did not have any statistical significance but ownership of a bicycle and having more off-farm income meant households were less likely to be food insecure. Addressing rural food security issues should consider the differences within the contexts of rural areas. Policies to support the improvement and diversification of farm and off-farm incomes, and increasing farm output have important implications for low-income farm households. Such initiatives could include improvements in transport infrastructure and access to credit, both of which would support market access, augment farm production and improve off-farm income. However, such policies and strategies would be more robust with more tests.