This study examined the effects of water quality and coral community structure on the prevalence and severity of two coral diseases, growth anomaly (GA) and coral tissue loss (TL) at five sites surrounding Hawai'i Island. The prevalence and severity of GA and TL varied significantly among the five sites surveyed but overall much lower than other global sites. The difference in disease levels among sites was expected as the sites represented a wide range of Hawai'i Island coral reef environments and corals are known to exhibit species-specific susceptibility to these diseases. Our analyses identified seven individual factors (coral colony size, colony density, species diversity, depth, temperature, salinity, and the concentration of ammonium) that were significantly correlated with the prevalence and/or severity of GA and/or TL among specific species and sites surveyed. Overall prevalence of GA among all sites increased with colony size. However, at each site, different factors significantly correlated to GA levels. At Kailua, colony size, colony density, and species diversity correlated with the prevalence of GA but not with the severity. At Ka'ūpūlehu, depth correlated the prevalence and severity of GA. At Richardson's Beach Park, colony size and species diversity correlated with the prevalence and severity of GA. At Wai'ōpae, temperature correlated with prevalence and severity of GA. On the other hand, the overall prevalence and severity of TL among all sites correlated with colony size, species diversity, depth, and ammonium concentration. However, different factors were significantly correlated with TL levels at each individual site. At Kailua, colony density was the only factor to correlate with the prevalence and severity of TL. At Kaloko, the severity of TL correlated with temperature, salinity, and ammonium concentration. At Ka'ūpūlehu, colony size correlated with only TL prevalence; while at Wai'ōpae, none of the environmental and ecological factors correlated to either the prevalence or severity of TL. Overall, the sites surveyed for this study have low levels of disease prevalence and severity of GA and TL. The correlative factors identified from this present study may change in the future if coral disease prevalence and severity increases. Therefore, it is important for comprehensive epizootiological studies to be conducted in Hawai'i in order to identify and mitigate key correlative factors that increase disease susceptibility before detrimental outbreaks and mortality occur. This study is the first to perform a complex quantitative investigation of the relationships among coral disease levels of GA and TL and environmental and ecological factors on Hawai'i Island. We hope this work will provide a framework for future studies and improve the understanding of coral health dynamics in Hawai'i.