Digestibility, performance and carcass analysis trials were used to compare the nutritive value of two diets, containing 78 % of either cooked potato flake (diet CPF) or maize meal (diet M). Diet CPF had slightly lower values for gross energy (GE) and nitrogen (N), markedly lower values for ether extractives and crude fibre, a slightly higher lysine concentration and a markedly higher potassium concentration. Apparent digestibility coefficients were determined with ten piglets weighing 22 kg; digestibility values for GE and N were respectively 0.95 and 0.91 for diet CPF, and 0.84 and 0.88 for diet M. Digestible energy (DE) and digestible N (DN) values were 10.2 MJ and 26.9 g/kg dry matter for diet CPF, and 15.3 MJ and 27.9 g/kg dry matter for diet M. The performance of 30 piglets grown from 21 to 53 days of age and from 6.0 to 13.1 kg was similar for each diet, as were the empty body, water, N, lipid, ash and GE gains of 18 of these piglets. The efficiencies of conversion of nutrients ingested from diet CPF into the components of body gain were for GE, DE, N and DN; 0.21, 0.22, 0.48 and 0.52 respectively. Corresponding values for diet M were 0.17, 0.21, 0.38 and 0.44. The greater efficiency with which the nutrients in the potato flake were used thus resulted in a growth response which was at least equal to that of the maize meal.