Removal of microplastics is one of the most important task in the modern society because the microplastics not only adversely affect the natural environment and ecosystem, but also have internal inflammatory and carcinogenic effects on the human body. Therefore, there is an urgent need to develop a method for recovering microplastics dissolved in aquatic ecosystems. Herein, polyvinyl alcohol (PVA) and polyoxomethylene (POM) microplastics dissolved in Tancheon, Seongnam were recovered by density screening using NaCl, an eco-friendly method. The density of the experimental aqueous NaCl solution was adjusted to 1.2 g/cm³. Pulverized PVA and POM was used for experiments, and the floatability was measured by comparing the initial input amount and the recovered amount. The floatability of microplastics was compared by changing the temperature and pH. The experimental results showed that the floatability of PVA increased as the temperature increased or the solvent was acidic or basic. On the other hand, the floatability of POM is high at low temperature or neutral pH condition.