The article presents the experience of 19 Russian medical institutions on the use of eribulin in combination with trastuzumab in various treatment lines of metastatic HER2+ breast cancer in routine clinical practice. Aim. The main objective of this retrospective observational study was to evaluate the efficacy and tolerability of eribulin and trastuzumab combo in HER2+ breast cancer patients pretreated with anthracyclines and taxanes. The analysis included 60 patients who received at least 2 cycles of eribulin in combination with trastuzumab. 2 patients (3.3%) received treatment as the 1st line, as the 2nd 14 (23.3%), as the 3rd 16 (26.7%), and as the 4th and more 28 (46.7%). Materials and methods. Complete response was achieved in 2 (3.3%) patients, partial response in 9 (15%), stable disease in 33 (55%), stabilization for more than 6 months in 11 (18.3%), disease progression was detected in 16 (26.7%) patients. The objective response rate was 18.3% in the whole group, the clinical benefit rate 36.7%. Results. The objective response rate in the group of the luminal subtype (ER/PR+HER2+) was 26.9%, in HER2-overexpressed subtype (ER-PR-HER2+) 8.8% and 64.7%, respectively, disease progression was recorded 2.3 times more often 35.3% versus 15.5% in the luminal subtype group. The median progression-free survival in patients with HER2+ breast cancer was 4.95 months (95% confidence interval CI 3.048.29 months), in luminal subtype 6.38 months (95% CI 3.338.54 months), in non-luminal 4.44 months (95% CI 2.47.96 months); p=0.306. The treatment was well tolerated, the spectrum of adverse events corresponded to the eribulin toxicity profile. Conclusions. The uniqueness of this study lies in the fact that on a large clinical material from the standpoint of real clinical practice, a very promising treatment regimen that is not used routinely in a number of countries has been studied, its effectiveness and satisfactory tolerance have been confirmed.