Purpose: The objective of the present study was to determine oral health knowledge, attitude and practice among National Cadet Corps (NCC) Navy Cadets and their correlation with oral hygiene in South India. Materials and Methods: A questionnaire study was conducted among 412 high school students who were voluntary participants of an NCC unit in South India. Knowledge, attitude and practice scores were calculated, and then were correlated with Simplified Oral Hygiene Index (OHI-S) values. Spearman's correlation test was used to measure the correlation. The significance value was set at P 0.05. Statistical analysis was performed using the Statistical Package for Social Sciences software for Windows, version 13. Results: NCC Cadets' knowledge about gum diseases and the use of fluoride-containing dentifrice was found to be low, dental visits were infrequent and the consumption of sweets was found to be high. There was no correlation between knowledge and attitude scores with that of OHI-S, but a significant correlation was seen between practice and OHI-S scores. Conclusions: Most of the cadets did not have knowledge about the causes and the prevention of dental diseases. A significant number of participants sought further information, hence it can be said that the cadets had a positive attitude towards oral health. There was no correlation seen between knowledge and attitude scores with that of OHI-S measured, but a significant correlation was noted between practice and OHI-S scores. Keywords: attitude, correlation, NCC Cadet, India, oral health knowledge, oral hygiene