During March 27th to April 4th, 2016, Heyuan experienced a pollution episode. The pollution process was studied based on the meteorological data and air quality monitoring data during this period. The results showed that, ρ（PM_2.5）/ρ（PM₁₀） and ρ（PM_2.5）/ρ（CO） in Heyuan on March 30th were 0.87 and 0.08 respectively, apparently higher than those on other days, implying the remarkable aging and secondary transformation characteristics. In the two different periods of the episode, PM_2.5 concentration fluctuations in Heyuan were affected by various meteorological factors, among which, PM_2.5 concentrations were apparently negatively correlated (R2=0.646 2）and inapparently positively correlated (R2=0.006 5) with air pressure succesively, inapparently positively correlated with temperature（R2 was 0.008 4 and 0.033 9 respectively）, weakly negatively correlated (R2=0.105 2）and inapparently positively correlated (R2=0.072 9) with wind speed succesively, and weakly positively correlated (R2 =0.391 3) and weakly negatively correlated (R2 = 0.176 9) with relate humidity succesuvely. Besides, comparisons of PM_2.5 concentration variation trends between Heyuan and surrounding cities together with the backward trajectory analysis showed that, the pollution episode in Heyuan was resulted from both local source emissions and PRD regional air pollution transmission.