The nutritive value of heat-dried brewery's activated sludge as swine feed was evaluated by determining digestibility with sows and by a feeding experiment with growmg pigs. The chemical composition of the sludge used in this experiment was similar to that of the sludge used in previous experiments in chickens, i.e., 37.6% of crude protein (CP), 0.8% of crude fat (CF), 28.1 % of nitrogen-free extract CNFE), 3.5% of crude fibre (CFib) and 18.0% of crude ash. The apparent digestibility of the sludge was evaluated using chromic oxide as an index with 4 sows. A feeding experiment was performed with growing pigs in 2 trials. The feeding period was from 8 to 26 weeks of age in each trial. In the first trial growing pigs were given the diet containing the sludge at 5 % level from 8 to 15 weeks of age; thereafter the level of the sludge was reduced to 3 %. In the second trial the feeding of the sIudge at 5% was prolonged to 17 weeks of age to take account of growth. The resuIts obtained were as follows: The apparent digestibility of the sludge was 67.4% of CP,75.7% of CF,56.3% of NFE and 23.7% of CFib and the estimated digestible crude protein and total digestible nutrients (TDN) were 25.3% and 43.3% respectively. No detrimental effect was observed in the growing pigs receiving the diet containing the sludge. As the resuIts of this study, though the TDN value of the sludge seems not to be very high for swine feed, it is possible to use the heat-dried brewery's activated sludge as a protein source in the diet of growing pigs to the extent used in this study.