Background: Growth hormone (GH) SNPs are associated with breast cancer and colon cancer. The author investigated the association of prostate cancer with genetic polymorphisms in GH SNPs in the Ancillary MrOS study. Methods: Included in the current investigation were 128 men with prostate cancer and 743 healthy men, 65 years of age or older. SNPs were tested in Growth Hormone 1 (GH1, n=4), Growth Hormone Receptors (GHR, n=15), Growth Hormone-Releasing Hormone (GHRH, n=4), Growth Hormone-Releasing Hormone Receptors (GHRHR, n=10), Ghrelin (GHRL, n=8), and Growth Hormone Secretagogue Receptor (GHSR, n=9) genes for an association with prostate cancer risk. SNPs were selected based on HapMap Phase 1 and based on functional variation. The SNPs were genotyped using Illumina Assay and were included if the minor allele frequency was 1% or greater. Logistic regression analysis was used to examine associations, adjusted for age, weight, BMI, truncal % fat, total % fat, and diabetes. Similarly, tests of trends and tests of dominant/recessive effect were performed. Results: After adjusting for potential confounding factors, two GH1 SNPs, one GHR SNP, one GHRH SNP, two GHRHR SNPs, one GHRL SNP, and one GHSR SNP showed significant associations with prostate cancer risk. Public Health Significance: If the relationships observed in this study are confirmed, it would justify the investigation of approaches that would reduce the activity of GH in those at high risk for prostate cancer. Conclusions: The results of the current study suggest that GH SNPs are associated with prostate cancer risk. This provides support for replication of these findings in other studies