Ambient concentrations of PANs and other related air pollutants were monitored at an urban site in Beijing each August from 2006 to 2014. The NO_x concentration decreased at a rate of 1.7 nL/(L/yr) (about 4%/yr), and the PAN concentration decreased at a rate of 0.03 nL/(L/yr) (about 3%/yr), while the O₃ concentration increased at a rate of 1.5 nL/(L/yr) (about 4%/yr), indicating that the measures taken to cut NO_x were effective for controlling PAN concentration. Beijing needs to strengthen the control of VOCs with reducing NO_x emissions for reducing O₃ concentration.