The dietary potassium requirements of weaning kittens given basal diets containing either a "normal" (33%) or "high" (68%) level of protein were determined. Potassium as KHCO3 was added to give concentrations of 0.1, 0.2, 0.3, and 0.4% for the 33% protein diet and 0.3, 0.4, 0.5, and 0.6% for the 68% protein diet. Excluding the highest concentrations of potassium used, body weight gains within diets were positively and linearly related to potassium concentration. Within both levels of dietary protein, concentration of potassium is plasma was linearly related to dietary potassium; however, for the same dietary potassium concentrations, kittens receiving the high protein diet had lower concentrations of potassium in plasma than kittens given he normal protein diet. Body weight gains were greater for kittens given the 68% protein diets than those receiving the 33% protein diet. The dietary potassium requirements of kittens were estimated as being in the range of 0.3% to 0.5% for 33% and 68% protein diets.