A study was realized to determine the response of Taro (Colocasia esculenta var antiquorum) to spacing at two levels of fertilization at San Carlos, Costa Rica. Ten spacing in the range from 0,2496 to 0,8609 m2/plant were systematically arranged in split plots with fertilizer (50-50-50 kg/ha NPK) or without it. No interaction was found between fertilization and population densities. Fertilizer application increased yield 30%. As spacing was increased, the weight and the number of shoots pet plant were increased. Density of 0,246 m2/plant allowed for the highest net income.