A vehicle steering system is provided which includes a variable angle ratio mechanism for changing an angle ratio of a steering angle of a steering member to a turning angle of a steering mechanism, the variable angle ratio mechanism including a first sun gear connected to a steering column, a second sun gear connected to the steering mechanism, and planetary gears each having a first toothed portion and a second toothed portion which are adapted to mesh with the first and second sun gears respectively, and are arranged to be spaced apart from each other in a tooth face width direction, the first toothed portion and the second toothed portion being formed integrally through forging.