Introduction. Due to insufficient efficacy of medical therapy of idiopathic secretory male infertility there is a need to develop and apply more resultative methods of treatment.
 The aim of our study was to assess the efficacy of low-level laser therapy (LLLT) in red spectrum on sperm parameters, sperm DNA fragmentation (SDNAF) and MAR-test rate in men with idiopathic infertility.
 Patients and methods. 85 men with idiopathic infertility were examined, 50 of them (first group) were treated with LLLT and 35 (second group) didnt have course of LLLT. Average age of patients of the first and second groups was 31.4 1.3 and 32.3 1.4 years. LLLT was performed in red spectrum on a Rubin-C device (Russia). 10 laser therapy procedures were carried out every two days with active luminescence for 10 minutes of both testicles. Male hormone panel, semen analysis, MAR-test, SDNAF were assessed before and after the treatment.
 Results. LLLT in patients of the first group resulted in significant increase in ejaculate volume, sperm viability, number of morphologically normal sperm forms (by an average of 11, 9 and 23% respectively), and active mobile sperm forms by an average of 14 and 19% one and two months after the therapy respectively. In 12 patients of the first group with initially increased SDNAF its level became normal after the treatment. Significant decrease of MAR-test we searched out in patients of the first group with its initial level less than 30%. As a result of the treatment, pregnancies developed in 10 (20%) out of 50 couples in the first group.
 Conclusions. LLLT in red spectrum leads to significant improvement of sperm quality in patients with idiopathic infertility, normalizes sperm DNA-fragmentation level and decreases MAR-test level.