The article presents the results of biochemical indices changes of connective tissue metabolism (oxyproline, oxylizine) in the vaginal walls in women with stress urinary incontinence after Er:YAGlaser treatment (technologies IntimaLase and IncontiLase). Conducted the examination and treatment of 77 patients with SUI light and medium gravity in age from 23 to 76 years (average age 49,8±11,6 years), of whom 58 patients identified I type, 19 II type of SUI (J.G. Blaivas, E.J. McGuire, 1988). The procedure of treatment consisted of circular radiation each 5 mm of vagina with four SMOOTH pulses for three passes (IntimaLase) and exposure of each 5 mm front wall of the vagina in chessboard order (IncontiLase). The course of treatment consisted of two procedures with 21 days interval. To assess the state of connective tissue collagen 26 patients before and after treatment (52 samples) was performed needle biopsy of back and front vaginal walls in the middle third outside the projection of large vessels and nerves to a depth of 1 cm, with the subsequent chromatographic study of the received material. When chromatographic study of 52 vaginal wall samples, the content of free hydroxyproline and oxylizine before treatment was 8,4±0,4 mkmol/g of tissue and 5,4±0,3 mkmol/g of tissue after treatment revealed a decrease in their number: 5,3±0,5 mkmol/g of tissue and 3,7±0,6 mkmol/g of tissue respectively (the differences are statistically significant, p< 0,05), which indicates a decline in the rate of collagen decay and evidence of its stabilization in the connective tissue. Marked biochemical changes (slow degradation of collagen) confirm the clinical efficacy of the method (the positive effect was obtained in 70,7% of patients with I type of UI and 47% with the II type of UI light and medium gravity).