Objective: We used health insurance research data in Taiwan to conduct a propensity-score matched study that included 17,055 patients with admissions for KD who received care by nephrologists and 17,055 patients with admissions for KD who received care by NN physicians. Multivariable logistic regressions were conducted to calculate adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for 30-day mortality and major complications associated with physician specialty. Methods: Compared with NN physicians, care by nephrologists was associated with a reduced risk of 30-day mortality (OR 0.29, 95% CI 0.25-0.35), pneumonia (OR 0.82, 95% CI 0.76-0.89), acute myocardial infarction (OR 0.68, 95% CI 0.54-0.87), and intensive care unit stay (OR 0.78, 95% CI 0.73-0.84). The association between nephrologist care and reduced admission adverse events was significant in every age category, both for sexes and various subgroups. Results: Patients with admissions for KD who received care by nephrologists had fewer adverse events than those who received care by NN physicians. We suggest that regular nephrologist consultations or referrals may improve medical care and clinical outcomes in this vulnerable population. Conclusions: Objective: The influence of physician specialty on the outcomes of kidney diseases (KDs) remains underexplored. We aimed to compare the complications and mortality of patients with admissions for KD who received care by nephrologists and non-nephrologist (NN) physicians. Methods: We used health insurance research data in Taiwan to conduct a propensity-score matched study that included 17,055 patients with admissions for KD who received care by nephrologists and 17,055 patients with admissions for KD who received care by NN physicians. Multivariable logistic regressions were conducted to calculate adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for 30-day mortality and major complications associated with physician specialty. Results: Compared with NN physicians, care by nephrologists was associated with a reduced risk of 30-day mortality (OR 0.29, 95% CI 0.25-0.35), pneumonia (OR 0.82, 95% CI 0.76-0.89), acute myocardial infarction (OR 0.68, 95% CI 0.54-0.87), and intensive care unit stay (OR 0.78, 95% CI 0.73-0.84). The association between nephrologist care and reduced admission adverse events was significant in every age category, both for sexes and various subgroups. Conclusions: Patients with admissions for KD who received care by nephrologists had fewer adverse events than those who received care by NN physicians. We suggest that regular nephrologist consultations or referrals may improve medical care and clinical outcomes in this vulnerable population.