Disclosed is a cart-attachable mobile golf bag, in which the golf bag is configured such that a head cover is detachably attached to an upper portion of a bag body storing golf clubs therein, and the golf bag is attached to a cart in a docking manner by engagement between a docking recess of the golf bag and a docking block of the cart inserted into the docking recess in a one-touch manner, thus making it possible that the golf bag is simply and firmly attached to the cart without requiring any separate tying process. In particular, the golf bag has a hard-shell structure, thus being safe even without requiring a separate wrapping cover when transported by air while being excellent in durability, and further the golf bag provides various storage spaces for storing various equipment other than golf clubs, thus being excellent in use efficiency.