Let A be a set in R3. A is called a Convex set in accordance with the coordinate planes ,if and only if ,any parallel plane to any coordinate planes was intersected with A is convex set . In this research we introduced a new style in the convexity is convexity in accordance with the coordinate planes ,and got a some of results and theorems, the most important : proving that every convex set in accordance with the coordinate planes is convex set, and we have offered many examples that illustrate the relationship between starshaped set, compact set , simply connected set , coordinate convex set and convex set in accordance with the coordinate planes .