We estimated the maintenance food requirements and examined the response to shortterm (38–64-h) food deprivation of larval walleyeStizostedion vitreumin the laboratory. First-feeding larvae (10.0–10.7 mm total length; 0.74–0.82 mg mean dry weight) required maintenance rations,Rmaint, of 7–11%·d−1when feeding on cyclopoid copepods at 15–22°C. Estimates ofRmaintincreased with water temperature. Based on theseRmaintestimates and functional response models from a previous study, we estimated that the prey (cyclopoid copepod) abundances,pmaint, necessary to allow walleye larvae to attainRmaintwould decline from 10 to 27 prey·L−1for larvae of less than 1 mg dry weight (<10.9 mm) to less than 2 prey·L−1for larvae of 1.5 mg or more dry weight (> 11 .9 mm). The effects of food deprivation varied with walleye body size and water temperature. The highest rates of mortality and weight loss were observed in larvae of 1.5–3.5 mg dry weight (11.9–14.6 mm), and the rate of weight loss increased significantly with increasing temperature. Energy densities (J·mg−1) of walleye larvae declined with body size but were not significantly affected by food deprivation or water temperature. Mortality rates were positively related to rates of weight loss during food deprivation.