This study examined the effects of message framing (gain and loss) and character/background color combination (a red background with white characters and a white background with black characters) on participants' perception of promoting materials and hence their willingness to receive the vaccine when they read the materials on the H1N1 Flu. A 2 × 2 between subjects experiment was used. 120 university students participated in the study. Results of the study show that participants are more interested and can better understand and tend to believe vaccine information presented through loss-framed messages, and loss-framed messages in combination with a white background with black characters will increase participants' willingness to receive the vaccine. Practical application of the two factors in the development of effective health promoting materials is discussed.