PURPOSE: To efficiently obtain a large sliver by dividing a lap into two small laps on a detaching roller with compressed air jets, gradually winding the edge ends of the laps to form slivers, and then gathering the slivers in the lower end portion of the detaching roller.

CONSTITUTION: This method for dividing a lap at the outlet of a linear comber for a long fiber comprises applying compressed air jets perpendicularly directed to the travel direction of a lap 1 to divide the lap 1 into two small parts to form the parallel separated small partial laps 8, when the lap 1 is formed on a detaching leather 3 with a detaching roller 2, gradually winding the edge ends of the small laps 8 to form small slivers, guiding the formed small slivers from the downstream of the detaching leather 3 into at least one funnel, and then gathering the small slivers in the funnel 5 to form at least one large sliver. Thus, the sliver having a good strength and a cohesive property is obtained.