Background: To examine associations between phenotypes of short sleep duration and clinically-assessed health conditions in long-term survivors of childhood cancer. Methods: Survivors recruited from the St. Jude Lifetime Cohort (n=911; 52% female; mean age 34 years; 26 years post-diagnosis) completed behavioral health surveys and underwent comprehensive physical examinations. Sleep was assessed with the Pittsburgh Sleep Quality Index. Short sleep was defined as <7 hours per night with phenotypes of short sleep including poor sleep efficiency (<85%), prolonged sleep onset latency (≥30 minutes), and wake after sleep onset (≥3 times per week). Covariates included childhood cancer treatment exposures, demographics, body mass index, and physical inactivity. Separate modified Poisson regression models were computed for each health category to estimate relative risks (RR) and 95% confidence intervals (CI). Multinomial logistic regression models examined associations between sleep and an aggregated burden of chronic health conditions. Results: Short sleep duration was reported among 44% (95% CI 41%-47%) of survivors. In multivariable models, short sleep duration alone was associated with pulmonary (RR=1.35, 95% CI 1.08-1.69), endocrine (RR=1.22, 95% CI 1.06-1.39) and gastrointestinal/hepatic conditions (RR=1.46, 95% CI 1.18-1.79), and anxiety (RR 3.24, 95% CI 1.64-6.41) and depression (RR=2.33, 95% CI 1.27-4.27). Short sleep with prolonged SOL was associated with a high/severe burden of health conditions (OR=2.35, 95% CI 1.12-4.94). Conclusions: Short sleep duration was associated with multiple clinically-ascertained adverse health conditions. Although the temporality of these associations cannot be determined in this cross-sectional study, sleep is modifiable, and improving sleep may improve long-term health in survivors.