This paper describes the flow past an inclined flat plate of finite width with the attack angle placed on a ground plane. The experiment was carried out in the 800 mm diameter Eiffel type wind tunnel having the working section of 1.5m length at Reynolds number of 5.1×104 mainly. The surface pressure distributions on the flat plate and on the ground plane around the flat plate were measured, and the drag coefficient, lift coefficient and side force coefficient were determined from them. The power spectrum of the X component of fluctuating velocity was measured to check the arch vortices shedding behind the flat plate. Consequently, it is found that the appearance of shedding arch vortices is in the range of 45°≤β≤120° for W/H=2 and β=90° for W/H=4 when α=30°, while the drag coefficient attains maximum near β=90° and the lift coefficient decreases for W/H=2, 4 and 7, as β increases from 30°to 135°.