This study was performed to survey on the prevalence of swine internal parasites at 12 piggeries being operated by the sawdust fermentative pigsty in Kyongnam central area. To investigate the effects of viability of eggs, larva and cysts, temperatures at the underlayer of the sawdust floor and rooms of pens were taken four times each season for one year. In a pig farms which have been operated by the sawdust fermentative pigsty, eggs of Ascar is suum(8.8%), Trichr is suis(18.3%), Oesophagostomum sp(9.4%), Strongyloides ransomi(1.3%), Hyostrongylus sp(3.8%) and Metastronylus apri(2.3%) were detected from 480 heads of Pigs. Cysts and oocysts of Coccidia(12.7%), Balantidium coli(5.4%) were also detected form 480 heads of pigs. The change of the temperature in the pig room was variable between $13^{circ}C; to; 27^{circ}C$ accord-ing to outside condition, whereas that in underfloor was consistently stable between $28^{circ}C ;to; 31^{circ}C$ which was strictly suitable for the development of eggs, larva and cysts.