Based on transport characteristics of air mass 72h back trajectories and statistical data filtered method, measurement data of atmospheric CH₄ obtained at Shangdianzi (SDZ) regional background station in Beijing during 2010 and 2014 were analyzed for non-pollution and pollution events. About 42% of the complete data set was filtered as pollution data, and the remainders not polluted by local emission sources were flagged as "representative background data". Variations of background CH₄ concentrations at SDZ station can be obtained based on the "representative background data". The annual mean background CH₄ concentrations varied from 1884.0×10^-9 in 2010 to 1916.4×10^-9 in 2014 observed at SDZ, with the averaged growth rate of 8.5×10^-9/a. Background atmospheric CH₄presented obvious seasonal fluctuations, the higher and lower levels of seasonal CH₄ cycle appeared in Jan-Feb and Jun-Jul, respectively, with the peak-to-peak amplitude of 32.8×10^-9. The seasonal variations of atmospheric CH₄ might be owing to the variations of OH concentration in atmosphere. Furthermore, the annual and "detrended" monthly CH₄ background concentrations observed at SDZ were higher than those of MBL at the same latitude and WLG global baseline station.