4‐(2‐Methoxyethyl) phenol (MEP) plays an important role in the formation of secondary organic aerosols (SOA). The gas‐phase mechanism and kinetics of MEP with OH reaction are studied by the density functional theory (DFT). The initial reactions of MEP with OH radical produce two different channels: OH addition and H abstraction. Subsequent reaction schemes of the main intermediates are investigated by using M06‐2X/6‐311++G(3df,2p)//M06‐2X/6‐311+G(d,p) level. Ketene, diketones and nitrophenol compounds are demonstrated to be the dominant oxidation products in the presence of high O2 and NOx. The total and individual rate constants are calculated by using the traditional transition state theory (TST) at 298K and 1atm. The calculated value of 5.62×10−11 cm3 molecule−1 s−1 is close to experimental data of similar systems. The lifetime of MEP is estimated to be 4.94 hours. These results provide a comprehensive explanation for atmospheric oxidation pathways of MEP.