To stably carry the golf bag by the wheels by improving an disadvantage of a conventional golf bag with wheels.

A wheel unit for a golf bag includes a pair of axle shafts 5a and 5b having wheels 4a and 4b respectively attached to ends so as to freely rotate, an axle shaft support means 8 for supporting the pair of axle shafts and slidingly guiding between two positions of a contraction position in which the wheels come near to each other and a space between the wheels is minimum and an expansion position in which the wheels are moved away from each other and the space between the wheels is maximum, wheel space adjusting means 10, 11a, 11b, 13a, 13b, 14a and 14b provided in one or both the axle shafts or the axle shaft support means to respectively independently slide the axle shafts and fix the axle shafts to the contraction position or the expansion position, and fastening and fixing means 17 to 22 for fastening and fixing the axle shaft support member to the bottom part of the golf bag.