Background This study assessed the impact of infectious diseases consultation (IDC) on 30-day readmission rates in patients with Staphylococcus aureus bacteremia (SAB). Furthermore, this study also evaluated the effect of IDC on adherence to guideline-directed therapy. Methods This retrospective cohort study enrolled 149 adult patients with SAB. Cohort 1 included 28 patients without IDC. Cohort 2 included 121 patients with IDC. Primary end point was all-cause 30-day readmission rates. Secondary outcomes included adherence to guideline-directed therapy and hospital length of stay (LOS). Guideline-directed therapy included repeat blood cultures until blood sterility, assessment for an echocardiogram, and appropriateness of antimicrobial therapy (including antibiotic, dose, and duration). Results Readmission rates were 46.4% (13/28) without IDC and 19% (23/121) with IDC (P = 0.006). Guideline-directed therapy occurred in 21.4% (6/28) without IDC versus 96.7% (117/121) with IDC (P = 0.0001). The average LOS was shorter without IDC than with IDC (5.6 vs 7.8 days, respectively; P = 0.01). The most common reasons for lack of guideline adherence in the control group were lack of echocardiogram (72.4%) and lack of repeat blood cultures (51.7%). Multivariate analysis demonstrated that only lack of IDC significantly affected readmission rates (odds ratio, 3.51; 95% confidence interval, 1.48–8.52; P = 0.0048). Conclusions Consultation with infectious diseases reduces 30-day readmission rates in patients with SAB and increases adherence to guideline-directed therapy; however, LOS was increased. Infectious diseases consultation should be considered for all patients with SAB.