Abstract Objectives Systemic inflammatory response syndrome (SIRS) is a common finding after cardiovascular interventions. Data on the incidence of SIRS and its impact on outcome in patients undergoing transcatheter edge-to-edge mitral valve repair (MV-TEER) for mitral regurgitation (MR) is lacking. Methods From January 2013 to December 2020, 373 patients with moderate or severe MR undergoing MV-TEER were included. SIRS was defined as at least two of the following criteria within 48 h after the procedure: leucocyte count > 12.0 or < 4.0 × 109/l, respiratory rate > 20 breaths per minute or PaCO2 ≤ 4.3 kPa/32 mmHg, heart rate > 90 bpm and temperature > 38.0 °C or < 36.0 °C. The primary endpoint was 3-years all-cause mortality. Results SIRS was observed in 49.6% (185/373) of patients. Patients who developed SIRS presented more frequently with NYHA III/IV at baseline [SIRS: 82.4% (149/185) vs. no SIRS: 79.0% (147/188); p = 0.029]. Patients who developed SIRS spent more days on ICU (p < 0.001) and overall length of stay was longer (p < 0.001). Relevant residual MR, defined as MR ≥ III in-hospital, was present more often in patients who developed SIRS [SIRS: 11.3% (20/177) vs. no SIRS: 3.93% (7/178), p = 0.036]. At 3 years, all-cause mortality in the entire population was 33.5% (125/373) with an increased all-cause mortality in patients with SIRS compared to patients without SIRS (HR 1.49, [CI 95% 1.04, 2.13]; p = 0.0264). In the multivariate analysis development of SIRS (HR 1.479 [CI 95% 1.016, 2.154]; p = 0.041) was identified as predictor for 3-years all-cause mortality. Conclusions SIRS is a common finding after MV-TEER occurring in approximately half of patients. SIRS after MV-TEER was associated with a longer in-hospital stay. In addition, we observed an increased 3-years all-cause mortality in patients with SIRS. Graphical abstract