One of the most difficult problem in clinical diagnosis is to differenciate albuminuria found in urine by mass-examination, especially on the point of harmlos albuminuria or renal diseases. Total 13,304 cases including 5,037 female students were examined in every years during 1967 to 1970. Albuminuria was found in 561 cases including 141 female cases, its total percentage in 4 years was 4.21% ranging from 1.86% to 5.80% in each year. Re-examinations were done in 320 cases of this group with 98 female cases, including anamnesis, urinalyses, blood pressure measument, PSP test, total serum protein & A/G ratio, ASLO, serum chloeserol, blood urea nitrogen and hematotrit. Albuminuria was ranged from 20.3% to 48.5% and 32.1% in average. Microhemauria and abnormal casts were found in 35.1% and 31.7% in avarage, respectively. Most cases of micro hematuria and abnormal casts were observed every times in the same cases, and about a half of negative cases of them became positive at the next examination. Decreased value of PSP excretion at 15 minutes and at 120 minutes were found in 10.8% and 5.7%, respectively. Decreasing tendency of PSP excretion at 15 minutes in the second examination was found in 5.5% . Low hematocrit value was revealed in the range of 1.9% to 7.3% and 4.6% in average. Abnormality of ASLO value was found in the range of 2.9% to 13.3% and 9.4% in average. High serum cholesterol value observed in the group was ranged from 3.3% to 9.0% and 6.1% in average. Abnormal cases in serum total protein and A/G ratio were 12.4% and 9.8% in average, respectively. Hypertension was found to be 5.8% in average in the maxium blood pressure: and 6.9% in average in the minimum. 42.9% of examined cases had no paticular anmnesis: and 29.0% of the cases had the history of chronic tonsillitis, 12.0% of them had renal diseases, and 11.1% of then had toothcaries. No sexual differences were observed statistically in each items of the examination. Diagnosis established in 126 cases were 36 cases of nephritis, 10 cases of essential hypertension, 16 cases of anemia and 17 cases of transient albuminuria. According to the results, it is difficult to prognose albuminuria during such a short period, but it is the most important thing to establish the diagnosis through the process of repeated urinalysis.