Previous research has suggested that problematic Internet use (PIU) is associated with impulse control disorder. Although researchers have suggested that impulsivity is a risk factor for PIU, the literature lacks longitudinal evidence on the relationship between impulsivity and PIU. We aimed to use a cross-lagged analytic framework to identify temporal order effects and hypothesised that impulsivity was the precedent factor for PIU. In a panel sample of college students (N = 367), trait impulsivity and PIU were measured in the spring of freshman year and in their junior year. The measures included a self-developed PIU Scale and the revised Impulsiveness Scale based on Barratt's concept. We found that “non-planning impulsivity” was not associated with PIU. The “motor impulsivity” subfactor was thus adopted in the cross-lagged model. The results suggest that motor impulsivity and PIU were stable across time. Motor impulsivity at Time 1 positively predicted PIU at Time 2, but PIU at Time 1 did not predict motor impulsivity at Time 2. A further investigation using gender as a moderator found a gender difference in the temporal relationship. Because motor impulsivity is a risk factor for PIU, potential prevention strategies based on this result are suggested.