Cardio-renal syndrome is a challenging clinical entity to manage, and is often associated with increased morbidity and mortality. We hypothesized that adaptive servo-ventilation (ASV), non-invasive positive pressure ventilation that ameliorates systemic/pulmonary congestion, may improve renal function in patients with symptomatic heart failure complicated by the cardio-renal syndrome. Patients with symptomatic congestive heart failure who underwent ASV therapy for over 1 month were included in this retrospective study. The trajectory of the estimated glomerular filtration ratio (eGFR) between the pre-1 month period and the post-one-month period (on ASV) were compared. A total of 81 patients (median 65 years old, 65 men) were included. eGFR decreased during the pre-1 month period from 52.7 (41.7, 64.6) down to 49.9 (37.3, 63.5) mL/minute/1.73 m² (P < 0.001) whereas we observed an increase following one-month of ASV therapy up to 53.4 (38.6, 68.6) mL/minute/1.73 m² (P = 0.022). A reduction in furosemide equivalent dose following the initiation of ASV therapy was independently associated with increases in eGFR with an adjusted odds ratio of 13.72 (95% confidence interval 3.40-55.3, P < 0.001). In conclusion, short-term ASV therapy was associated with the preservation of renal function, particularly when the dose of loop diuretics was concomitantly reduced.