In today’s life technology concerned with robots plays an important role in many fields because they are used to operate in hazardous and urban environments,for security,in traffic system,rescue mission as well as military operations.Some of the robots are designed to operate only on natural terrains,but it can also used for rough terrains and artificial environments including stairways.This article represents the mechanism of how will robot climb stairs carrying load.Its mechanical design is suitable with front and back wheels driven by DC motors for climbing stairs.Until recent years,the stair climbing robots are designed with vast hardware and robots are equipped with chain roller to climb stairs or to move on a flat surface.The mechanical design of this robot contains gear train one it her side of chassis with fixed wheel legs instead of a chain roller moves relative to each other to generate high friction with stairs.