Hyperprolactinemia is one of the most frequent endocrine disorders in women of reproductive age and is accompanied by menstrual irregularity, impaired fertility and other manifestations. Data on the prevalence of this disorder has been mainly obtained in referral (selected) samples of women and population data is still limited. Objective: to investigate the prevalence of hyperprolactinemia in unselected population of premenopausal urban women from Eastern Siberia. Methods: we performed institution-based, cross-sectional study. A total number of 249 premenopausal urban female employees, aged 31.17 ± 6.34 years, were underwent obligatory yearly medical assessments from March 2016 till November 2017 in Irkutsk and Ulan-Ude cities (Russian Federation). All women signed informed consent and were evaluated in a consecutive manner. History obtained included age, obstetric and gynecological history, previous morbidity, medications use, as well as any complains. Physical exam included weight, height, blood pressure and other vital signs, gynecologic exam, blood samples. Serum prolactin as well as TSH concentrations were measured by ELISA. Hyperprolactinemia was diagnosed in patients with prolactin level higher than upper normal limit (600 mIU/liter). Study was approved by the Institutional Ethics Committee. ANOVA, Mann-Witney tests, χ2 test and Fisher's exact test were used for statistical analysis (Statistica 6.1). A p < 0.05 was considered statistically significant. Data is presented as Mean(SD) and n/N(%). Result: Among all 249 examined women 35 (13,94%) demonstrated hyperprolactinemia with serum prolactin concentrations higher than 600 mIU/liter: 860.06 (381.16) mIU/liter compared to 312.56 (126.06) mIU/liter (p < 0.05) in 216/249 (86.06%) women with normal prolactin. Subclinical hypothyrosis prevalence was not significantly higher in hyperprolactinemic women - 2/35 (5.71%) vs their comparators - 10/216 (4.63%), p >0.05. It was shown that menstrual disfunction did not strongly correlate with prolactin level as well as frequency of breast-related complains which were similar in women with and without hyperprolactinemia (10% vs 18.8 %, p >0.05). Conclusions: According to our data moderate idiopathic hyperprolactinemia in unselected urban female population is not rare but it is not strongly associated with such “classic” clinical manifestations as menstrual disorders and mastalgia.