Unplanned hospital readmissions are common early post-kidney transplantation. We investigated the relationship between early hospital readmissions and clinical outcomes in a single-center retrospective study that included all adult kidney transplant patients between 2004 and 2008 with follow-up to December 2012. The early hospital readmissions within the first 30 d were numbered and the diagnosis ascertained. Patients were grouped as none, once, and twice or more readmissions. Predictors of early readmissions were assessed, and clinical outcomes and patient and death-censored kidney survival were compared. Among 1064 patients, 203 (19.1%) patients had once and 83 (7.8%) patients had twice or more readmissions within 30 d. Surgical complications, infections, and acute kidney injuries/acute rejection were three most common diagnoses. The length of initial hospital stay and African American race were among the variables associated significantly with readmissions. Patients with early readmissions had lower baseline renal function (p < 0.01) and more early acute rejection (p < 0.01). During follow-up, only frequent readmissions, twice or more, within 30 d were associated with increased risk of death (AHR 1.75, p = 0.01) and death-censored kidney failure (AHR 2.20, p < 0.01). Frequent early hospital readmissions post-transplantation identify patients at risk for poor long-term outcomes, and more studies are needed to understand the mechanisms.