In order to estimate the densities and composition of floating marine debris (FMD), a sighting survey was conducted from July 1st to July 14th, 2009 in the East China Sea (ECS) using a training vessel "Kaya (1,737 ton)" of Pukyong National University. The sampled zones are divided into 5 transects by observation day during the survey days and the densities and composition in each transect were calculated using the numbers of item per $km^2$. The results of distribution of FMD are as follows: 1. During the surveys, a large variety of FMD was discovered and highest densities were found in the Central East(CE) of the East China Sea(ECS) (48.2 items/$km^2$), whereas densities in the less populated transects in Okinawa(OK1, OK2) were comparatively low(3.5 ~ 4.9 items//$km^2$). 2. Among the classified 6 items, styrofoams(Styro) were most abundant and ubiquitous(10.3 items/$km^2$, 53% of the total number), except OK2 area. Next abundant item was vinyl and plastics called V & P(4.9 items/$km^2$, 25%). Above 2 items of the major proportion of FMD accounted for 78% of the total number of FMD observed through this study. 3. The percentages of manufactured plastics(Styro and V & P) found in the Seas near Korean Peninsula were varied from 87.2% to 69.8%. It was recognized that polluted level is middle value among them.