Pragmatics as a field of linguistic science helps us understand how language is used, what it is used for and it’s meaning in a given context. Therefore, health posters are peculiar means of communicating information about diseases, identifying risk factors and promoting behavioural change. Language use aids healthcare providers to shape and define ‘normal and healthy’ behaviours and conditions. This study therefore aims at doing a pragmatic analysis of selected health posters so as to establish the relationship between the visuals and the captions of the posters and the relevance of the principles of meaning in the posters. Three health posters cutting across different diseases were collected and analysed, using Sperber and Wilson’s Relevance Theory. It involves the analysis of direct and indirect relevance of pragmatic principles in the health posters. The study discovers that colour combination in the health posters communicates the desired message of the health care providers. The study also revealed that the health posters are informative and educational despite that, some of them appeared vague and ambiguous.