Cellophane noodles, or fensi, sometimes called glass noodles, are a type of transparent noodle made from starch and water. A stabilizer such as chitosan may also be used.

They are generally sold in dried form, soaked to reconstitute, then used in soups, stir-fried dishes, or spring rolls. They are called "cellophane noodles" or "glass noodles" because of their cellophane- or glass-like transparency when cooked.

In 2004, a number of companies producing Longkou cellophane noodles produced in Yantai, Shandong were discovered to be adulterated, with unscrupulous companies making noodles from cornstarch instead of green beans in order to reduce costs; the companies, to make the cornstarch transparent, were adding sodium formaldehyde sulfoxylate and lead-based whiteners to their noodles.

In December 2010, Czech food inspection authorities (SZPI) again inspected Chinese cellophane noodles, this time determining that 142 mg/kg (0.00227 oz/lb) of aluminium had been used in the production of the noodles. Above 10 mg/kg (0.00016 oz/lb) is an illegal amount for noodles in Czech and EU markets.

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