To provide a road surface (floor slab) line erasing machine less producing noise and dust pollution and capable of peeling off coating in a short time when coated lines on a road surface or a plant floor surface are erased.

A rotary grinding means 2 for grinding the lines on the road surface (floor surface) is disposed at the front part of a body 1 formed so as to be able to run by itself or manually, and a blasting means 3 for projecting shot blasts against the ground lines is disposed at the rear of the body 1. A blast collection means 4 for sucking both line paint dust peeled off by the grinding and shot blasting and the shot blasts is arranged continuously with the blast means 3.