The total protein in urine from young boys before and after exercise was measured by spectrophotometry, using the TONEIN-TP reagent, and at the same time by naked-eye colorimetry. Both methode were performed without delay after the urine was excreted. The latter method is simpler than the usual methods. In order to confirm the reliability of the naked-eye colorimetry, total protein in the urine of factory workers was also determined. The following results were obtained: 1. The total protein in the urine of young boys before and after exercise was measured immediately after excretion in the field using a portable spectrophotometer. The young boys between the ages of 15-17 trained and rested together at a lodge during the summer of 1981. They belong to a basket ball or judo team. 2. It was confirmed that the increase in urine albumine was greater after exercisee than before by single radial immunodiffusion assay. The value of total protein and albumine in urine correlated well, especially in tests after exercise. 3. The author devised a simple method in which the TONEIN-TP reagent was added to the urine and coloration was determined with the naked eye instead of with a spectrophotometer. There was no statistical difference between the two methods. 4. The measurement of total protein in urine from workers was done by the TES-TAPE and the naked-eye methods. The latter method was more sensitive(5mg/dl) than the TES-TAPE (30mg/dl) method, so it is thought to be convenient when quick measurements are required. This method using the TONEIN-TP reagent was simple and sensitive. Moreover, the urine was. used immediately after being excreted in the field, therefore, it was not necessary to worry about a chemical change occuring during preservation of the urine.