The study investigated the impact of farming systems on determinants of smallholder sugarcane farmers (SSFs) financial sustainability (FS) between Block Farming (BF) and Traditional Farming (TF) systems. FS was analyzed by assessing profitability of the farming system. Semi structured questionnaires were administered to a random sample of SSFs and officials of block farms within Kilombero valley in Morogoro region in the south eastern Tanzania. 1040 observations from 394 respondents for SSFs’ FS have been analyzed at significance level of p = 0.05. Two sample t-Tests, one way ANOVA and Tobit regression analysis performed revealed that effects of the two farming systems on the hypothesized factors differs significantly. Yield, price and cost have been found to have significant effects on financial sustainability, whereas the effect of land size and sucrose were not significant.BF has been found to be significantly more effective than TF system in ensuring profitability of the farmers. Profitability through BF is 0.56 (56%) as compared to 0.39 (39%) through TF.