Abstract:In Southwest China, the road surface fluctuates greatly, which has a great influence on the real driving emissions. In this paper, RDE (real driving emission) tests on four routes of different cumulative positive elevation gains were conducted by using a light-duty gasoline vehicle that meets China-6 emission regulation standards. The correlation between cumulative positive elevation gainor dynamic parameter v·apos[95] of road section and window and pollutant emission factors (CO, CO2, NOx and PN) was analyzed.The results show that the correlation between pollutant emissions and cumulative positive elevation gain or v·apos[95] was not strong in the road section. In the window, when v·apos[95] was large, there was a significant correlation between CO emission and cumulative positive elevation gain. CO2 emission increased with the increase of cumulative positive elevation gain, and was less affected by v·apos[95]. No significant correlation was found between NOx emission and cumulative positive elevationgain or v·apos[95]. In the range of high v·apos[95], PN emission had a significant correlation with cumulative positive elevation gain,while in the range of low v·apos[95], PN emission had no significant correlation with cumulative positive elevation gain. The suggestion is to set different limits on the cumulative positive elevation gain of urban, rural and motorway sections.