The health medical costs of colorectal cancer are increasingly higher in Taiwan. The National Health Insurance Administration (NHI) and The Health Promotion Administration of the Ministry of Health and Welfare (MOHW) in Taiwan encourage individuals to adopt an earnest approach to healthy behavior through advocacy advertising. However, the number of colorectal cancer patients continues to increase annually. Our study explored the effects of health-related advertisements (ads) on healthy behavior intentions as influenced by regulatory focus theory (RFT) and construal level theory (CLT). We conducted an experiment with different public health advocacy ads. A 2 (regulatory focus: promotion vs. prevention) × 2 (temporal distance: one month vs. one year) × 2 (graphics-text ratio: more pictures and less text vs. fewer pictures and more text) three-factor experiment was adopted. The multiple analysis of variance (MANOVA) results revealed that ads with higher construal levels (i.e., more text) had greater effects with a promotion-oriented regulatory focus. However, no significant differences were found in either attitude toward the ads or behavior intention when the regulatory focus was prevention. In addition, according to the young testers and those who were psychologically distant from colorectal cancer, different temporal distances and different construal levels had no statistically significantly effects on attitudes toward advertising or on behavior intentions. The results revealed that viewers found the information easier to understand when the ads triggered the regulatory focuses of the viewers and applied an appropriate graphics-text ratio, which resulted in favorable health-related advertising effectiveness. Thus, we provide two suggestions regarding the use of health-related advertising for MOHW in the future.