Two experiments were conducted to determine the dietary methionine requirement of weanling pigs fed diets containing spray-dried porcine plasma and(or) blood meal in a phase-feeding program. In Exp. 1, 216 crossbred pigs (21 +/- 2 d of age and 4.9 kg BW) were fed diets (1.6% lysine, .52% cystine) containing 10% spray-dried porcine plasma and 1.75% spray-dried blood meal from d 0 to 21 postweaning. Pigs were fed one of six dietary treatments ranging from .28 to .48% total dietary methionine (.225 to .425% apparent digestible methionine). From d 0 to 14 and d 0 to 21 postweaning, ADG, ADFI, and gain:feed ratio (G:F) increased (quadratic, P < .01) as dietary methionine increased. Inflection point analysis projected .42 and .41% total dietary methionine to maximize ADG and G:F from d 0 to 14 and d 0 to 21 postweaning, respectively. In Exp. 2,216 crossbred pigs (21 +/- 3 d of age and 5.6 kg BW) were used to determine the dietary methionine requirement from d 7 to 28 postweaning. All pigs were fed the same diet (1.6% lysine, .44% methionine, .52% cystine) from d 0 to 7 postweaning. From d 7 to 28, pigs were assigned to one of six dietary treatments (1.3% lysine, .46% cystine) containing 10% dried whey and 3% spray-dried blood meal. Total dietary methionine levels ranged from .27 to .42% (.249 to .399% apparent digestible methionine). From d 7 to 14 postweaning, increasing dietary methionine increased (quadratic, P < .05) ADG, ADFI, and G:F (.34 to .35% total methionine projected by inflection point analysis).(ABSTRACT TRUNCATED AT 250 WORDS)