The research was conducted to analyze the current farming situation and financial efficiency of grown maize on paddy rice farming land in the Vietnamese Mekong delta in the case study in Chau Thanh district, Soc Trang province. The study data were collected from 45 households growing maize on rice land by convenient sampling collection method. The methods were used, including descriptive statistics, cost-benefit, and correlation regression analysis. Research results showed that the model farming of cultivated maize on rice land brought high production efficiency. The average maize yield per hectare/crop was an average of 21,273 maize fruits/ha. While the total cost of maize cultivation per hectare/crop was an average of 24,749,000 VND/ha, the profit without family labor was an average of 36,370,000 VND/ha/growing season. The profit included family labor households ranging from -3,470,000 to 83,027,000 VND/ha/growing season. The maize productivity model depended on many factors in which hired labor and agrochemicals dose were positively correlated. The profit model depended on seed, hired labor, agrochemicals dose, and family labor costs. Besides these advantages, maize production in the district also faces many difficulties, including the price of inputs and output, the consumption of the market, and low technology production of the household scale.