Objectives: Despite advances in critical cares over the past decades, outcomes of patients with severe acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) remain poor. Appropriate starting of CRRT and preventing relevant complications may improve their outcomes. Several studies have revealed that consultation to a nephrospecialist in patients with kidney diseases is related with improved survival and low risk of hospitalization and complications. However, it remains undetermined whether consultation to nephrospecialist is related with survival benefit after starting CRRT due to AKI. Methods: A total of 2,397 patients who started CRRT due to severe AKI were retrospectively collected from 2010 to 2020 at Seoul National University Hospital, Korea. The patients were divided into two groups according to the presence of consultation to nephrospecialist for the CRRT setting and maintenance. The Cox proportional hazard model was used to calculate the hazard ratio (HR) of mortality within the admission to intensive care unit (ICU mortality) after adjustment of multiple covariates. Results: 2,153 patients (89.8%) were consulted to nephrospecialists after starting CRRT. Despite adjusting multiple covariates, patients with consultation had lower mortality rate than the patients without consultation (HR = 0.474 [0.400–0.562]; P < 0.001). Subsequently, patients with consultation were divided into two groups according to the consultation time, such as early and late consultation. Both early and late consulted patients had lower mortality rates than the non-consulted patients with HRs of 0.447 (0.371–0.538) and 0.506 (0.421–0.609), respectively Conclusions: Consultation to nephrospecialist is associated with low risk of mortality after starting CRRT due to AKI. This relationship remains consistent irrespective of consultation time.