PROBLEM TO BE SOLVED: To obtain the subject covering sheet having a sufficient strength, proper air-permeability and water-permeability, capable of promoting the growth of a plant, without requiring the recovery of the sheet after harvesting, and improving the labor saving by applying a color hardly allowing the penetration of sunray on the surface of a specific nonwoven fabric sheet. SOLUTION: A color hardly allowing sunray to penetrate, such as a black one is applied at least on one surface of a nonwoven fabric sheet produced out of a biodegradable fiber containing 0.5-30.0 wt.% chitin and chitosan and having 25-80 g/m2 weight. The biodegradable sheet for covering the soil surface is preferably composed of a nonwoven fabric produced out of the biodegradable fiber colored with the color hardly allowing the sunray to penetrate.
