Indian agriculture is known for its multi-functionalities of providing employment, livelihood, food, nutrient and ecological securities. The income from cropping alone on small and marginal farms is hardly sufficient to sustain the farmer's family with the decline in farm size (0.15 ha. /person) due to explosion of population and this situation gets further weakened due to failure of monsoon. The farmer, has to be assured of a regular income for a satisfactory living (above the poverty line), a judicious mix of any one or more enterprises with agronomic crops ensures better farm income. Therefore, in the present study, comparative economics of various farming systems have been workout for ascertaining the sustainability of most profitable one. The three widely adopted farming systems were selected for the study viz., I) Crops only, II) Crops + Livestock, III) Crops + Livestock + Horticulture crops. The two districts viz., Ahmednagar and Solapur were selected purposively. In Ahmednagar district, Sangamner tahsil was selected as irrigated tahsil and Pathardi tahsil was selected as rainfed tahsil. While from Solapur district, Pandharpur as irrigated tahsil and Sangola, as rainfed tahsil were selected. From each tahsil, three villages were selected, randomly and from each village, 15 farmers were selected in such way that, 5 farmers from each farming system (F.S.I-Crops only, F.S.II-Crops + livestock, and F.S.III- Crops + livestock + horticulture) were get selected. As such, 180 sample farmers were selected randomly for the study. The primary data were collected by survey method from the selected farmers with the help of specially designed schedules for the year 2007-08. The comparative picture of the employment pattern showed that, the employments generated were more in irrigated region as compared with the rainfed region because in irrigated region, irrigated crops such as sugarcane, wheat, fodder etc. required more labours. The own farm employment was more in farming system-III of irrigated region. In all the farming systems owned and hired male-female played significant role in crop production activity as compared to other activities of production. The per farm income pattern indicated that, the total income in farming system- II was double than the farming system-I, while total income of farming system- III was four fold than that of farming system- I. The total income from farming system- I (crop production activity) was very less as compared to farming system- II and III. The item wise income indicated that, the more than 50 per cent income was derived from crop production in farming system- I and II, while in farming system- III, more than 50 per cent income was derived from horticulture and in the farming system- I, 31.52 per cent income was derived from other than farm business activity but in farming system- II and III, correspondingly, just 3.09 and 1.79 per cent income was derived from other than farm business activity. This has indicated that farming system-I, depends more on other than farm business activity as compared to farming system- II and III. In expenditure pattern, out of the total expenditure more than 70 per cent was the farm expenditure in all the farming systems. The expenditure on crop production was the major expenditure in farming system- I and II, while expenditure on horticulture was major expenditure in farming system- III. The region wise total expenditure was more in irrigated region than the rainfed region. The economic sustainability depends on profitable enterprises, family saving and the family debt. The sustainable farm income means the annual income from farm activities which meets the annual expenditures of farm and family and remains surplus to the farm family for saving or repayment of debt. The region wise sustainable farm income indicated that, farming system- II and III, were having the sustainable farm incomes in both the regions. But farming system- I of irrigated and rainfed region could not meet their requirements on the basis of their farm business income i.e., income from crop production activity alone. They experienced a deficit in income. It means farmers of farming system-II and III of both regions were having sustainable farm income. But the farming system- I was not having sustainable farm income. After adding the income from other sources, farmers in farming system-I, had sustainable farm income, in both the regions. Therefore, the income from other sources (wages, service and business etc.) was the only factor, which helped them to become sustainable.