PURPOSE: To obtain a glass cloth preventing fray without using an organic solvent by providing a cut part with an allylamine polymer.

CONSTITUTION: The cut part of a glass cloth is immersed in or coated with a fray-preventing agent composed of an aqueous solution of an allylamine polymer having 2,000-500,000 molecular weight so as to provide the glass cloth with 0.8-8%, preferably 1-4% based on the weight of the glass cloth of the cut part of the fray-preventing agent and dried to fix the fray of the cut part.