The effect of temperature on the nitrogen removal performance of the sequencing batch reactor technology is evaluated for tannery wastewater. The study involved the operation of a pilot-scale sequencing batch reactor installed on site to treat the plain-settled effluent. The nitrogen balance of the system is observed for a wide temperature range between 9 to 30degreesC. The results are evaluated by means of model calibration of COD, nitrate and ammonia nitrogen concentration profiles during cyclic operation. The fates of the major nitrogen parameters are also interpreted on the basis of fundamental stoichiometry for nitrification and denitrification.