Application of crop rotation method in fish farming provides an opportunity to increase fish productivity and crop yield in ponds. In the Middle Eastern countries, in recent years, the method of aqua-crop rotation, in particular the sequential cultivation of fish and rice in finishing ponds, which allows eliminating the contradictions between these crops and increasing the efficiency of production, has been developing. In Iraq, an experiment was conducted on the alternating cultivation of rice and carp in finishing ponds for four years to introduce this method into the country's agriculture. Four ponds with an area of 7.5 ha each were involved; the studies were conducted in two variants: in experiment No. 1, rice was grown in the first year, fish in the second year, then rice again and fish in the fourth year; in experiment No. 2, vice versa, fish first, then rice, etc. The fish breeding season lasted nine months (from March to November). Fish breeding indicators were studied in detail: survival rate, feed costs, fish productivity, and the results of rice cultivation were judged by yield. In addition, cost-effectiveness indicators were determined by a simplified scheme. The results indicate that, in general, fish breeding performance was higher when fish were raised in ponds after rice. Thus, fish productivity increased by almost 30% with an average of 3.9 t/ha, feed costs decreased, while rice yields also increased by 15-16% to an average of 3.6 t/ha. The best fish breeding indicators were obtained in the second experiment after rice was grown in the ponds for two years. Economic calculations have confirmed the advantages of the aqua-crop rotation method. Thus, in the second experiment, the cost of commercial fish decreased by 10%, while profitability increased by almost 30%.