In order to develop a mower attached to the front of speed sprayer, a mowing part was developed separately for power operation. A prototype mower is composed of height adjusting wheels, straight blades(600 mm), gasoline engine(16HP) and the attachment to a speed sprayer. The FE modeling of frame panel is implemented. The maximum Von-Mises stress is 39.33 Mpa at hydraulic system and minimum Von-Mises stress is 0.02 Mpa at the center of frame panel. A safety factor of 6.3 would be adequate for a drive component in a mower.