The present study was carried out to evaluate the effects of replacing fish meal with dietary Arthrospira platensis as a feed supplementation on growth performance, survival and skin pigmentation of guppy, Poecilia reticulata. A total number of two hundred forty healthy fishes (average body weight 0.15±0.02) were equally divided into four feeding groups (triplicates) as such as control (T0), 5% (ST1), 10% (ST2) and 15% (ST3). The final experiment was conducted in aquarium for 60 days. The average crude protein and Crude lipid levels of the diet is 10.31 & 39.81%, respectively. A significant increase in the concentration of carotenoids in fish skin was observed with an increase in spirulina concentration in fish feed. However, the ST3 treatment had highest carotenoids concentration. Redness, yellowness and whiteness found to have significant differences. There was a significant difference between treatment groups concerning the growth parameters. The ST3 diet significantly increases length, weight, net weight gain, weight gain, specific growth rate and survival rate. Inclusion of 15% Spirulina was found to be suitable to ensure growth as well as pigmentation of guppy. Spirulina powder can be used as protein and carotenoid supplements in fish feed to improve growth, survival and colouration of guppy.