The exhaust emission profiles of regulated gases, PM, PN and 2.5PN for the latest HD engine equipped with DPF and Urea SCR system were investigated. The profiles were observed in long range and included DPF regeneration. The NOx emission increase was observed during the regeneration due to falling NOx removal efficiency of the SCR system. PM, PN and 2.5 PN emissions were also increased in the cycle with the regeneration. The results of PM composition analysis using ion chromatography indicated the ratio of nitric acid ion was high corresponding to NOx removal by urea-SCR. The main species in the exhaust which contained nitric acids is not nitrate ammonium.