A new species of ciliates Hemiophrys polymicronuclei sp. nov. from Donghu Lake is described. It is characterized by its colorless to yellowish, soft, flat and spindle-shaped body with four micronuclei. The right side of the body is a little more convex than the left side, and more transparent at both anterior and posterior ends. Its slit-like cytosome accounts for 1/4 to the body length on the left side without any trichocyst. There are two rows of trichites near the right anterior end, 6-8 straight bristles on the pellicle opposite the cytosome, 23-25 rows of kinetides on the right side of the body, two ellipsoid macronuclei and many contractile vacuoles in the cytoplasm.