In pointing tasks using a mouse, the pointing time is affected by the size of the target. Studies of typical pointing tasks assume that the operator’s gaze intersects the target surface perpendicularly. However, if the target surface is tilted and the operator’s gaze does not intersect perpendicularly with the surface, the perceived width of the target decreases depending on the tilt angle. This study investigated whether perceived target width influences pointing time. We also examined the effects of the subject’s gaze either focusing solely on the target or alternating between the starting point and the target. A small angle of target tilt had no significant effect on pointing time: there was no effect when the target was tilted at 30 degrees, but pointing time was affected when the target was tilted at a larger angle (60 degrees). Fitts’ law for pointing task time showed higher explanatory power when perceived target width was used to account for target tilt. Additionally, the effect on effective target width was similar when performing Fitts’ task while focusing on the target and when alternating the gaze between the starting point and the target. However, pointing task performance was better when the gaze was fixed on the target compared to when the gaze alternated.