The objective of this experiment was to study effects of dietary crude protein and crude fibre levels on N, and P excretion, hydrogen sulphide, ammonia and greenhouse gases emission from the slurry of growing pigs. The experiment was conducted on 30 growing pigs Duroc x Fl (Landrace x Yorkshire) with initial body weight of 34.7 + or - 2.6 kg. The experiment was arranged as randomized complete block design with two factors. Dietary crude protein included three levels of 17, 15 and 13 percent; dietary crude fibre included two levels of 8 and 10 percent. Each treatment combination was repeated 5 times, each in one block. Air samples, emitting from slurry pits, were analysed to identify NH3, H2S and greenhouse gas emission. Slurry samples were analysed for slurry characteristics. Results showed that reduced dietary crude protein levels from 17 percent to 15 percent did not affect pig performance, however further reduction to 13 percent reduced pig performance (P0.05). Reduced dietary crude protein levels from 17 percent to 13 percent reduced slurry pH from 6.66 to 6.27; reduced 28 percent N excretion in the slurry (P0.05), however no effects were found in P excretion in the slurry (g/pig/day). Increased dietary fibre from 8 to 10 percent did not affect slurry pH, N and P excretion in the slurry (g/pig/day). Decreased dietary crude protein from 17 to 13 percent reduced 70 and 68 percent NH3 and H2S emission from the slurry, respectively. Dietary crude protein and fibre levels did not affect greenhouse gas emission (P0.05). Reducing dietary crude protein levels can be considered as a solution to reduce environmental problem at the source.