Colorimetric method of protein determination in urine with use of pyrogallol red (PGR) has certain advantages over a routine method of proteinuria determination with use of sulfosalicylic acid (SSA) which is still applied in most clinics in the Russian Federation. For the purpose to determinate the diagnostic significance of proteinuria estimation by different methods at pregnants with preeclampsia, conducted a comparative research of proteinuria levels at 68 pregnants with preeclampsia and at 15 healthy pregnant by two methods: with sulfosalicylic acid and with pyrogallol red. At the same patients the diagnostic significance of protein/creatinine ratio was evaluated when using the method with PGR. It was revealed that proteinuria determination with PGR- method had authentically higher sensitivity, and proteinuria indices when using this method corresponds to the criteria for evaluation of preeclampsia severity specified in the Ministry of Health Russian Federation Order No. 572n 2012 and the Clinical Recomandations “Hypertensia during pregnancy. Preeclampsia. Eclampsia” (2012). In case of proteinuria determination by method with SSK it is necessary to consider lower sensitivity of the method and adhere to earlier classification of preeclampsia (gestosis) where proteinuria more 1 g/l was regarded as the symptom of severe preeclampsia. Confirmation of the diagnostic significance of protein/creatinine ratio needs further researches. (For citation: Mozgovaya EV, Androsova NE, Dorofeicov VV. Compared diagnostic value of proteinuria definition applying different methods at pregnants with preeclampsia. Journal of Obstetrics and Women’s Diseases. 2017;66(4):51-56. doi: 10.17816/JOWD66451-56).