Two experiments were conducted to evaluate energy value of spray-dried whole egg (SWE), albumen powder (AP), and effects of lysozyme (LZ) in diets containing these two protein sources. Experiment 1: 18 barrows were allotted to one of the three diets (Basal, SWE, and AP). Both digestible (DE) and metabolizable energies (ME) were lower (P < 0.01) in AP than SWE. Experiment 2: 120 piglets weaned at 21 d were allotted in a 2 × 2 factorial experiment. Diets contained either 8.0% SWE or 4.67% AP, supplying the same amount of crude protein and were fed with or without 1 g kg^-1 LZ. Supplementation of LZ in SWE and AP diets improved (P < 0.01) G:F than the diets without LZ. Lysozyme decreased (P < 0.01) Escherichia coli counts in cecum and Lactobacilli counts in both cecum and colon (P < 0.05). Lysozyme reduced serum IgM (P < 0.05), d-lactic acid (P < 0.01), and diamine oxide (P < 0.05). Piglets fed AP had lower (P < 0.05) serum urea nitrogen levels than those fed SWE. In conclusion, SWE contains higher DE and ME contents than AP. Lysozyme improved the performance of piglets by regulating the gut microflora, protecting the intestinal barrier and lowering immune activation.