Using the molecular dynamics simulations we study sliding friction of two-dimensional systems with atom electronegative difference. We show that systems with large atom electronegative difference exhibit larger friction than systems with similar structures but less polarity. We demonstrate that the sliding friction along polar paths gives larger friction than along nonpolar paths, and exhibits stronger stick–slip behavior. Due to inertia and thermal effects the sliding path deviates from the minimum-energy path. We show that the electronegative friction is reduced by thermal fluctuations and that it depends linearly on the logarithm of the sliding velocity. Our findings will supply insight into the nature of the friction in low dimensional systems, which could facilitate the design of nanodevices.