Nineteen black marsh turtles, Siebenrockiella crassicollis, confiscated by international authorities in Hong Kong, People's Republic of China, on 11 December 2001 were examined for endohelminths. Turtles were either frozen or placed on ice and shipped to the Texas Cooperative Wildlife Collection, Texas A&M University, College Station, Texas, U.S.A., for examination. Eighty-nine percent of the black marsh turtles examined was infected with helminthes, with an average of 1.6 species per infected turtle. Prevalences of collected helminths were as follows: 1 unidentified proteocephalid tapeworm (5%), 2 nematodes (Falcaustra duyagi [74%] and Serpinema octorugatum [21%]), 3 digeneans (Diaschistorchis multitesticularis [11%], Stunkardia dilymphosa [11%], and Telorchis cyclemidis [21%]), and 1 aspidogastrean (Multicotyle purvisi [26%]). Eggs from a species in Spirorchidae were also found in the intestinal wall of 1 turtle.