To evaluate childhood cancer survivors' adherence to surveillance protocols for late effects of treatment and to determine the factors affecting adherence.Between 2014 and 2016, 11,337 survivors and 2,146 siblings in the Childhood Cancer Survivor Study completed a survey ascertaining adherence to Children's Oncology Group (COG) guidelines for survivors at high risk for second malignant neoplasms or cardiac dysfunction and to the American Cancer Society (ACS) cancer screening guidelines for average-risk populations. Adherence rates and factors affecting adherence were analyzed.Median age at diagnosis was 7 years (range, 0-20.9 years), and median time from diagnosis was 29 years (range, 15-47 years). Among high-risk survivors, adherence to COG breast, colorectal, skin, and cardiac surveillance was 12.6% (95% CI, 10.0% to 15.3%), 37.0% (34.1% to 39.9%), 22.3% (21.2% to 23.4%), and 41.4% (40.1% to 42.7%), respectively. Among average-risk survivors, adherence to ACS breast, cervical, and colorectal screening was 57.1% (53.2% to 61.0%), 83.6% (82.7% to 84.5%), and 68.5% (64.7% to 72.2%), respectively. Twenty-seven percent of survivors and 20.0% of primary care providers (PCPs) had a survivorship care plan (SCP). For high-risk survivors, SCP possession was associated with increased adherence to COG breast (22.3% v. 8.1%; prevalence ratio [PR], 2.52; CI, 1.59 to 4.01), skin (34.8% v 23.0%; PR, 1.16; CI, 1.01 to 1.33), and cardiac (67.0% v 33.1%; PR, 1.73; CI, 1.55 to 1.92) surveillance. For high-risk survivors, PCP possession of a SCP was associated only with increased adherence to COG skin cancer surveillance (36.9% v 23.2%; PR, 1.24; CI, 1.08 to 1.43).Guideline adherence is suboptimal. Although survivor SCP possession is associated with better adherence, few survivors and PCPs have one. New strategies to improve adherence are needed.