<p>A top pipe cap for a slag dropping pipe of a boiler fixedly mounted on the top end of the slag dropping pipe (5) comprises supporting componets, a connecting componet and a pipe cap (4). The pipe cap (4) includes a column pipe cap body and a circular arc top cap (41) which are integratedly formed. At least one opening is set on the pipe cap (4). The supporting components comprise at least two supporting feet (1). One end of each supporting feet is connected with the top pipe wall of the slag dropping pipe (5), the other end is connected with the pipe cap (4) by the connecting component. The top pipe cap for slag dropping pipe of the boiler can slow down the falling speed of the slag. The abrasion caused by the slag on the slag dropping pipe (5) and the pipe cap (4) can be reduced. And the clogging of the slag dropping pipe by large size slag is also avoided.</p>
