A field survey was performed at the Human-made Wetlands along Boknaecheon of Juam Lake from March 2004 to October 2007 for the purpose of investigating changes of flora for 4 years since its creation. A total of 15 species including 10 families, 13 genera, 12 species and 3 varieties were planted at the Human-made Wetlands along Boknaecheon of Juam Lake which was completed in December 2002. The survey conducted in 2004, 15 months after creation of the Human-made Wetlands, revealed a flora composed of 47 families, 102 genera, 112 species and 19 varieties, 131 taxa in total. In 2007, further increase was registered with 46 species added compared to 2004 reaching 177 species in total. A 4-year monitoring of naturalized plants showed that no quick but constant increase was featured yearly in their number of species with 12 in 2004, 17 in 2005, 18 in 2006 and 19 in 2007. As for changes in life form, 13 species of perennial plants and 2 woody species, 15 in total, were planted initially but, in the survey 2004, 1- or 2-year old therophytes numbered 73, perennial plants 54 and woody species 4, indicating a large change of life form accompanied with increase in overall number of species. The number of 1- or 2-year old therophytes and perennial plants featured a steady increase each year from 2005 to 2007. The distribution ratio of 1- or 2-year old therophytes, however, showed a gradually decreasing tendency while perennial plants tended to increase, instead. As evidenced in changes of flora at the Human-made Wetlands, most of species in it have been determined to be fit or not within 1 to 2 years after its creation and, since the stable settlement of these species onward, its life forms have undergone stepwise changes together with the number of species and individuals in parallel with repeated extinction and penetration of plants.