Cambodia has been known as an endemic area for malaria and schistosomiasis (Meek, 1988; Singhasivanon, 1999; Urbani et al., 2002). The infection status of intestinal parasites in Cambodia, however, has not yet been thoroughly investigated. Only several reports show Cambodian refugees infected with intestinal parasites including nematodes, trematodes and protozoa (Nwanyanwu et al., 1989; Lurio et al., 1991; Gyorkos et al., 1992). With aids of a local Korean missionary in Cambodia and a medical service team from Wonju Christian hospital, we performed stool examinations. In February 2002, we collected 251 stool samples from Tonlebat primary school children in Kampongcham, Cambodia. Kampongcham city is located 80 km from Phnom Penh to the northeast. Formalin-ether sedimentation technique revealed intestinal helminth eggs of Ascaris lumbricoides, Trichuris trichiura, hookworm, Rhabditis sp. Echinostoma sp. and Opisthorchis sp., and protozoan cysts of Entamoeba histolytica, Entamoeba coli, Giardia lamblia and Iodamoeba butschlii, respectively. Of the 251 stool specimens, 136 (54.2%) were positives. The positive rates of boys and girls were 57.3% and 50.5%, respectively. Data revealed the highest positive rate as 26.3% for Ascaris lumbricoides, followed by 15.6% for Echinostoma species (Table 1). Multiple parasite infections were found in 16.7% of the stool specimens. There was no cestode infection. The infection rates ranged from 48.7% to 59.6% by the grade, and the highest rate was noticed in second grade schoolchildren. It was interesting to compare trematode infection with their eating habits. In general, they did not consume raw fresh water fish (Story and Harris, 1989), however, are thought to be infected by insufficiently cooked fish. Opisthorchis infection rate was 4.0%. Not only Opisthorchis species but also Echinostoma species were important trematode parasites in need of treatment. Anti-helminthics were sent to Tonlebat primary school after stool examination. The school is located along the Mekong river. Although, many children were swimming in the river during the stool examination we could not find Schistosoma eggs. Considering swimming habits, the area is considered to be no schistosomiasis endemic area.