The nutria(Myocastor coypus) that is originated from South America is a representative Invasive alien species in Korea. invasive alien species is one of the biggest causes for the loss of biodiversity and it may threaten the conservation and function of ecology as well as the welfare of mankind. Intense habitation has been made around the Nakdong River basin area that this study has analyzed the habitat density of nutria for the subject of 3 survey sites in the Nakdong River basin area. As a result of survey on habitation density in 2011 and 2012, under St.1 it was shown $2.01{pm}0.21$/ha in 2011 and $0.69{pm}0.55$/ha in 2012. Under St.2, it was shown $0.91{pm}0.37$/ha in 2011 and $0.55{pm}0.39$/ha in 2012. Under St.3, it was shown $5.31{pm}0.72$/ha in 2011 and $3.99{pm}2.31$/ha in 2012. The wet survey areas of St.1 and St.3 had shown relatively high habitation density compared to St. 2, the river survey area, and the average annual habitation density of the survey area was $2.74{pm}2.29$/ha in 2011 and $1.74{pm}1.18$/ha in 2012 that it has shown slightly reducing trend. As a result of measuring the morphology by capturing the habitation individuals, the average body length of adults is $92.23{pm}9.41cm$, the length from the head to body for $53.90{pm}5.15cm$, tail length for $38.33{pm}4.83cm$, hind foot length for $13.82{pm}1.00cm$, front foot length for $6.02{pm}0.56cm$, and weight for $5.48{pm}1.08kg$. As a result of comparing the types between genders, male showed a slightly higher figure in all parts compared to female and it showed significantly difference in total body length, head-body length, front foot length and total weight. As a result of analysis for each head-body length, other measured parts, weight and relativity for each measured part, all bodily part is shown to have the higher volume of correlations. The condition index of individuals in the survey area was shown in the average of $35.67{pm}4.78$ with female for an average of $36.60{pm}5.19$ and male for an average of $34.73{pm}4.34$. The winter temperature in the southern area of Korea is considered for not greatly impacting on the habitation and development of nutria that, if there is no artificial control, it is considered to have certain concern of showing drastic breeding and territory expansion for the habitation group.