The district unit planning (DUP) in Korea is a planning instrument. One of the key methods is the incentive system focused on the mitigation of the financial charge of business proprietors with use of various planning deregulation. Here in this paper, it is examined whether the incentive system is indiscriminately applied not only in the metropolitan cities but also in the rural cities. The analysis is carried out with six indicators in relation to the effect on the incentive system on the market of Apartment Housing Development. The indicators are a. the building-to-land ratio(BLR), b. the floor area ratio(FAR) c. the publicly assessed value of land(PAVL), d. the sale price of land(SPL), e. the sale/lease price of apartment house(SLPH) and f. the ratio of housing subscription(RHS). The final result is that the incentive system has different effects between metropolitan cities and rural cities. One of reasons lies on the too high FAR in rural cities to be given basically. Another reason lies on the difference between the cost for purchasing public installation and the profit of the sale & lease price of apartment house. In rural cities their difference becomes much narrow. Finally, the low ratio of housing subscription(RHS) in rural cities makes the effect of the incentive system nearby meaningless.