The author performed quantitative analyses of the amount of urine excreted, the urine density, pH's, microprotine content, urine protein content, the amount of Donaggio reaction-positive substance, urine creatinine, uric acid, urine lactic acid, urine phosphoric acid, and the urine calcium content in the urine before and after work, selected from various groups of persons such as a group of marathon runners, a group of soldiers marching, and a group of ammunition carriers; and obtained the following results. 1. In the group of marathon runners whose work is thought to be relatively intense and of a comparatively short duration there can be recognized a rapid decrease in the urine content, an increase in the amount of urine microprotein and in urine protein-positive cases, an increase in the hourly excretion of Donaggio reaction-positive substance, a rapid increase in the density and hourly excretion of lactic acid, a slight decrease in the density and the hourly excretion of creatinine, an increase in the density and hourly excretion of phosphoric acid, and a decrease in the density and hourly excretion of calcium. Judging these estimated values stoistically, it has become possible to obtain significant values in the Donaggio reaction and in the lactive acid with an error of less than one per cent in the hourly excretion contents and similarly significant values in the mucoprotein and phosphoric acid contents under 5 per cent deviation. 2. In the marching which is relatively of an intermediate degree of fatigue and of a longer duration, there can be observed a decrease in the quantity of urine, an incrase in the urine density, acidification of the pH, increase in the protein-positive cases; a transient increase and decrease in the excreation of creatinine and the hourly excretion amount, stability of the density and houly excretion of uric acid, a transient increase in the early stage uric acid, and a transient increase in the density and excretion of phosphoric acid. Namely, the substance estimated in this group tend to iucrease at an early stage of the marching but in the terminal stage they tend to return to the normal values. 3. In the group of munition carriers whose work is successive from day to day and is of a high degree, there can be recognized a tendency of relatively little change in the urine pH's, an increase in the donaggio value, a transient increase in the density and hourly excretion of creatinine, and also an transient increase in the quantity and hourly excretion of uric acid, revealing a tendency to become orientated to the daily successive labor.