The feasibility of cultivating Chlorella vulgaris with wastewater containing high ammonia nitrogen concentrations was examined. The average specific growth rate of C vulgaris was 0.92 d(-1) at 17 mg L-1 NH4+-N, but declined to 0.33 d(-1) at NH4+-N concentrations of 39-143 mg L-1. At 39 mg L-1 NH4+-N, lipid productivity reached a maximum value (23.3 mg L-1 d(-1)) and dropped sharply at higher NH4+-N levels, which demonstrated NH4+-N should be controlled for biodiesel production. C16 and C18 fatty acids accounted for 80% of total fatty acids. Increasing NH4+-N from 17 to 207 mg L-1 yielded additional short-chain and saturated fatty acids. Protein content was in positive correlation with NH4+-N content from 17 mg L-1 (12%) to 207 mg L-1 (42%). Carbohydrate in the dried algae cell was in the range of 14-45%, with a peak value occurring at 143 mg L-1 NH4+-N. The results demonstrate that product quality can be manipulated by NH4+-N concentrations of the initial feeds. (C) 2012 Elsevier Ltd. All rights reserved.