The study was set out on the thrust to examine the influence of cartoon in communication effectiveness. It should be noted that ever since the first appearance of a cartoon in a newspaper, it has remained one of the most integral parts of a newspaper. It plays different role depending on the type of cartoon and caption used. Cartoon to many is entertainment and funny graphics. Agenda Setting Theory was used to give theoretical depth to the study. Survey research method was adopted while some respondents were selected from the Nigerian Tribune newspaper with selected 100 respondents that were drawn using accidental sampling method. Findings showed that cartoons are often used in newspaper to set agenda on current issue and matters which may neither be expressed by news and features including editorial page. Respondents also admitted that due to the power and freedom enjoyed by cartoon that news, articles and editorial writers lack, makes it possible for cartoonists to use cartoon to tell what reporters and feature writers are afraid to write. The study recommended that more creative cartoonists be employed by newspapers houses in order to have more information and agenda setter cartoons.