Since about 1967, a polypropylene pipe that is 1.0mm in diameter has been used for weaving fancy mat in place of a rush. And the fancy-mat workers take extremely long working hours to weave it for the pursuit of profits. So, to clarify the relationship between the conditions of working and of their health, a survey was made on 118 workers (of whom, 52 males and 66 females) in 49 households in Seno-cho, Okayama Prefecture, in 1970. The results obtained were as follows: 1) As for the environment in the workshop, a noise level of weaving machines reached 80 phone. This value appeared to show the influence on the physical function of workers. 2) Admitted was want of sleeping hours among most of the workers because of irregular working hours, that is, over ten-hour labor a day (this contained 32.4% of the workers) and a working system of day-and-night shift. 3) Most of subjective fatigue complaints were the cases of chronic fatigue. The values of Donaggio's test of urine were high in 32.7% of the workers. 4) It was found mostly in the subjects of night-working type that values of Flicker descrimination varied more than 10% upward and found in the sujects of early-morning-working type that varied more than 10% downward. 5) As for the conditions of nutrition intake, it appeared that the side food was preferred to the staple food. This tendency is similar to an urban-type, though Seno-cho is located in a rural district.