Paromius exiguus (Distant, 1883) is a serious insect pest in rice field adjacent to reclaimed land. They suck young ear of rice causing empty head of grain or pecky rice grain. During 2010 to 2012, we conducted to investigate the host-plant change of P. exiguus in Siwha reclaimed land, Hwaseong-si. In 2012, we also studied dispersal ability of P. exiguus from reclaimed land to adjacent rice fields. In early May, the adults aggregated on the grain parts of cogon grass (Imperata cylindrica) (Poales: Poaceae) after overwintering, and laid their eggs and nymphs developed into adults on the same host plants from middle May to late June. Second generation was observed at wood small-reed (Calamagrostis epigeios) (Poales: Poaceae) from late June to late July. At shooting stage of rice, adults moved to adjacent rice fields and third generation might be started. Although dispersal ability of adult of P. exiguus penetrated about 10 km into inland areas of Hwaseong-si, number of individuals of P. exiguus population was significantly declined with increasing distance from reclaimed land (Pearson’s correlation coefficient, r=-0.7357, p<0.0001). Unfortunately, further studies on population dynamics of P. exiguus in rice fields could not investigated, because pesticides were widely sprayed by aerial application in 14 August, 2012. Nevertheless, this results will be a useful information for management and control of P. exiguus in rice fields adjacent to reclaimed land.