Testicular cancer incidence rates are increasing worldwide making it the most common malignancy in males aged 15 to 45 years. Without a known way to prevent the disease health professionals must promote awareness and early detection. A literature review identified a scarcity of information regarding awareness and knowledge of, and attitudes toward, testicular cancer and testicular self-examination among men in Northern Ireland. This study aimed to establish baseline data for Northern Ireland using a convenience sample of 150 men, aged 18 to 45 years. The sample was recruited from across the country and so represents a range of education and area deprivation levels. An online survey was used to collect data. Results showed that while 39% of respondents correctly identified the age group at highest risk for testicular cancer, only 17% of respondents had ever heard of a testicular self-examination. Analysis revealed knowledge, awareness, and attitudes differed by age groups and area deprivation quintiles. It is recommended that health promoters in Northern Ireland and elsewhere use these findings to tailor health promotion initiatives to engage men and raise testicular cancer and self-examination awareness.