An epidemiological study of clonorchiasis sinensis and paragonimiasis westermani prevailed among the people of a rural county. The author studied the infection rates of of clonorchiasis sinensis and paragonimiasis westermanl in the inhabitants of Chungsong Gun, Kyungbuk Province, Korea. The examinations were carried out from March 1965 to November 1965 fowards 1.303 inhabitants whose ages were ranging from three months to over sixty years. All the inhabitants were tested intradermally with clonorchis and paragonimus antigen and then confirmed the eggs by M. G. L. technique and sputum test. The results of the examination were summarized as follows : 1. Out of the persons tested, 15.8% were infected with clonorchiasis sinensis. 2. Out of the persons tested with paragonimus antigen, 20.9% were infected with Paragonimus westermani. 3. The infection rate of paragonimiasis was higher than that of clonorchiasis. 4. The infection rate of clonorchiasis in male was 20.8% (147 out of 706), while that in female was 7.1% (58 out of 597). The infection rate of paragonimiasis in male was 21.2% (150 out of 706), while that in female was 20.1% (120 out of 597). 5. The maximum infection rates of clonorchiasis and paragonimiasis were observed among the $45{sim}49$ age group (65.2% and 43.5%) respectively), however it was gradually decreased in the senile group. 6. By occupation, the maximum infection rate of clonorchiasis was observed in policemen (45.7%) and the maximum carrier of eggs (by sputum test) was observed in the unemployed (paragonimiasis). 7. By education, the maximum infection rate of clonorchiasis was observed in the unepmloyed (28.9%) and the maximum carrier of eggs (by sputum test) was observed in the unemployed (paragnoimiasis).