A ball collecting device comprising a drum and a control element. A first cover and a second cover are installed at both ends of the drum respectively to form a containing space in the drum. The first cover and the second cover are hollow and connected to at least one ring-shaped body with an interval apart. Each ring-shaped body comprises at least one elastic element installed around the ring-shaped body. The first cover, the second cover and the ring-shaped bodies are connected by at least one rod. The control element is connected to the drum and provided for a user to hold and push the drum to roll. An elastic element installed around the second cover is provided for pushing at least one ball to shift and enter into the containing space for storage, so as to provide a convenient way of collecting balls.