The morphological characteristics of Vorticella campanula attached on Eriocheir sinensis were redescribed by the observations of living bodies and protargol and silver nitrate impregnated bodies. Some new morphological supplemented characteristics were: One contractile vacuole was 7.5-8.7 μm in diameter. Freedom movements of some yellow, green, brown and black granules were within the protoplasm. Food vacuoles were 9-15 μm in diameter. Stalks were 5.1-7.6 μm in width. Myonemes were 2.7-3.2 μm in width, on which some black granules in the diameter of 0.5-0.7 μm were densely distributed. The clear striaes were on the outside of pellicle and the granulars were in the inside of pellicle. The outer two kineties were longer than the inner kinety of P3. The three kineties of P2 were equal in length and end of junction of P1 and P2. The outer two kineties were longer than the inner kinety of P1. The argyrophilic grains were obvious and densely and unevenly distributed. Phylogenetic analysis indicates that Vorticella campanula was more original than other Vorticella campanula and was divided from Vorticella at the earliest stage.