Town is very dynamic area. Growth of population, both natural and migration (urbanization), need area for the settlement and their activities. Neccessity of area for settlement can't be avoided. As a result, there is a landuse changing from non settlement area (wet field, dry field.swamp, pond) to settlement area. This change will influence the hydro system balance in Semarang, for instance the extending of flooding area, etc. This research tries to find the characteristic oflandusechange in Semarang. The charateristic involving how is pattern, process, intensity, and tendency. Pattern of landuse changing is sequence of using area before it became the settlement. Process of landuse chane is by using how the population are able to settle. Tendency is degree of land use change speed. This reseach methode is secondary analysesmethode, that is compare the statistic data of the landuse and map in 1980 and 2000. The sampling is by purposive random sampling rnethode. Purpusive is used so that all subdistrics in suburban are represented. The sample area is the from percil in certain coodinate. Result of this research shows that there is landusechanging rapidly that is decrease in the width of wet field, dry field, swamp and pond. On the other hand, there is increase in width of settlement area and other dry land with intensity 232 ha every years. Wet field decrease 131, 7 ha every years, swamp and pond 31 ha, and dry field 24,2 ha every years. In actually this landuse changing pattern is out of government policy. Semarang government's policy instrucs ttie settlement by using non productive land, but intead most of wet field are conversed. However, wet field is water habitat that is most potential. Tendency of settlement growth is more focus on accesibilit y aspect and available city's facilities only. Number of settlement are built on land which not suitable, such labile land, or high slope. It proves that the government control function is weak. The conclusion from this research that Janduse changing has to be controlled restrainded,so it will not cause the bad effect in Semarang. Width the wet field is 10 % by width town, must be conservation. Because wet field has ecology value and economic value that is rice production and absorb labour in agricultural sector. Ther2 e fore, function role of government controll must be actived.