The following results were obtained through the screening survey to detect the prevalence of hematuria & proteinuria in the healthy Korean schoolchildren. A total of 2,888 primary schoolchildren in Seoul, examined to be healthy by the author were tested for hematuria and proteinuria during the period of 3 months from Apr. 1979 to June 1979. Hemacombistix of Ames Company, U.S.A. was used in this examination. 1. The prevalence of hematuria detected with Hema-combistix was 1.97%(57 children) and that of microscopic hematrua was 0.93% (27 children). The prevalence of proteinuria was noted in 2.04%(59 children). 2. The prevalence of hematuria detected with Hema-combistix was higher in female children as 2.66% among 1,355 children, compared to 1.37% among 1,533 male children, which was ore prominent in the age 9 year-old group. The prevalence in female was higher than in male in all but 7 year-old age group. 3. The prevalence of microscopic hematuria was higher in female children as 1.40% compared to 0.52% in male. The prevalence was higher in female children in all but 7 year-old age group. 4. The correlation of tests of hematuria between Hema-combistix and microscopcy showed 85.2% in sensitivity and 59.0% in specificity. And there showed a statistically significant difference in the prevalence rates detected as above one positive in the both tests. 5. The prevalence of proteinuria was higher in female children as 2.8%, compared to 1.37% in male, which was more prominent in the 11 year-old age group. The age prevalence of proteinuria showed increasing frequency as age increases. The highest age prevalence was 1.94% in 12 year-old age group among males and 4.91% in 11 year-old age group among females. 6. The prevalence of co-existence of microscopic hematuria and proteinuria was 0.07%, which was noted in 2 cases in each 8 year and 10 year-old group. 7. Microscopic hematuria was present mostly in the range of one positive(5-20 RBC/HPF), which was prominent in female children. However, hematuria detected as above three positive (above 40 RBC/HPF) was found in male children. 8. Proteinuria was noted mostly in the range of one positive(30mg/dl) and the prevalence of proteinuria above 100mg/dl was 9.52% in males & 13.16% in females. And proteinuria above 300 mg/dl was noted in one male child.