Contamination resistant cyclic olefin container

The present invention relates to containers made of thermoplastic resins, and particularly to containers made of thermoplastic resins which are suitable for carrying wafers for the production of semiconductors in the production steps of semiconductors and which are inhibited from contamination of their contents. A container comprising a body made of a thermoplastic resin and a lid made of a thermoplastic resin, characterized in that at least one of the body and the lid is molded from a thermoplastic cyclic olefin resin. Said container hardly causes contamination of the content therein with water or organic substances permeating through the container from the outside or released from the container per se, and, besides, hardly causes contamination of the content with fine dust in handling.