PURPOSE: To obtain a dust collecting ship which has a simple structure and can be operated simply, by forming the inteior of the front part of a full into a dust collecting tank having the front surface opened, and installing a dust collecting equipment which consists of an arm shiftable back and forth and having a fork at the top end, at the front end of the dust collecting tank.

CONSTITUTION: In collecting the dust which floats on the water surface of dams or lakes, a fork 3 in the nearly parallel state to an arm 4 advances the arm 4 by means of an advance and retreat means (not shown), and a hull 1 is advanced in the direction where dust collects. An oil hydraulic cylinder 7 is operated in the state where the arm 4 is extended to the maximum, and the fork 3 is turned at right angles to the arm 4. Afterwards, the arm 4 is retreated in this state, and the dust between the fork 3 and the hull 1 are scratched into by the fork 3 and thrown into a dust collecting tank 2 in the hull 1.