The research aimed to compare different diet formulas on growth, carapace width and carapace length, cost and water quality were studied. The larval of Ricefield crab (Somanniathelphusa spp.) nursery were conducted in the plastic pond (100 L.), 12 ponds. Four treatments with three replications each CRD were applied including T1 Powder feed, T2 Powder feed+raw Arthrospira 30%, T3 Powder feed+Water meal 30%, T4 Powder feed+powder Arthrospira 3%. Larval Ricefield crab initially stocked were 0.05?0.01 gm/crab, in weight at a density of 200 fish/m2 and feed 10%/crab weight/day. Data was collected every 15 days for a 75-day period. It was found that larval Ricefield crab nursed with powder feed+ powder Arthrospira 3% had significantly (p < 0.05) higher average weight, average daily growth, weight gain, specific growth rate, survival rate feed conversion rate protein efficiency ratio carapace width and carapace length were better than other treatments. The cost of larval Ricefield crab nursed with powder feed (1.167?0.014 baht/crab) and powder feed+water meal 30% (1.233?0.014 baht/crab) were better than other treatments. The water quality of larval Ricefield crab nursed in all experiments were not significant difference and were in the aquaculture standard. It can be concluded that the Ricefield crab nursed with powder feed+ powder Arthrospira 3% had growth were better than other treatments.