This study was conducted to determine the replacement effect of spray dried plasma protein (SDPP) with dried porcine solubles (DPS) in weaning pigs. An ileal digestibility trial, at first, was conducted to formulate the experimental diets with SDPP or DPS. Six piglets (21-d old and 6.12kg BW) with T -cannula in the terminal ileum were used. In a feeding trial, 180 pigs (21-d old and 5.98kg BW) were alloted in a completely randomized block design. Treatments were T1 (SDPP 5%, DPS 0%), T2 (SDPP 5%, DPS 2.5%), T3 (SDPP 2.5%, DPS 0%), and T4 (SDPP 2.5%, DPS 2.5%) for phase I, and T1 (SDPP 3%, DPS 0%), T2 (SDPP 3%, DPS 1.5%), T3 (SDPP 1.5%, DPS 0%), and T4 (SDPP 1.5%, DPS 1.5%) for phase Ⅱ. Phase Ⅰ(0～1 week) diet was formulated to contain 3,300ME kcal/kg and 1.25% digestible lysine, and phase Ⅱ (2～3 week) diet contained 3,320ME kcal/kg and 1.10% digestible lysine. Chemical pompositions of the protein sources were higher in SDPP than DPS: CP (81.60 vs. 56.01), lysine (5.95 vs. 3.36), and methionine (1.85 vs. 1.22). Apparent ileal digestibilities of arginine, isoleucine, leucine, lysine, methionine, threonine and phenylalanine were higher in DPS than SDPP (p<0.05). The apparent ileal digestibility of essential amino acids (average) was also higher in DPS than SDPP (p<0.05). There were no significant differences (p>0.05) in ADG and ADFI of piglets during phase Ⅰ (0～1 week) and Ⅱ (2～3 week) among treatments. However, during phase Ⅱ, T2 showed better FCR than T1 (p<0.05). During the overall period, there was no significant difference in growth performance among treatments. When DPS was partially replaced for SDPP, the diet cost was significantly reduced (p<0.05) in terms of cost/kg of body weight. In summary, the digestibility of DPS was exellent, and it would be concluded that DPS can be partially replaced in the young pigs' diet containing SDPP in order to reduce diet cost in weaning pigs.