Abstract: For microplastics in the upstream of the Yellow River in Shanxi Province during dry season, the distribution characteristics of microplastics and the surface morphology of attached microorganism were characterized by scanning electron microscopy and metallurgical microscope, and polymer type of microplastics was analyzed by Fourier transform infrared spectroscopy, and community structure of attached microorganism in the microplastics was analyzed by high-throughput sequencing technology. The results show that the abundances of microplastics in the surface water and sediment are 160 n/L-275 n/L and 287 n/kg-480 n/kg, respectively. The particle size of most of plastics（70%） is smaller than 1 mm. Moreover, above 60% of microplastics are white, and the second are red and black microplastics（total content of 20%-30%）, and blue microplastics are least, only about 10%. In addition, a half of microplastics display nubbly, of which the main component is polypropylene; the proportion of fibriform microplastics are 30%-40% and their main component is polyethylene; the residuals of 10%-20% are filmy and globular and their main component is polystyrene. Scratches, grooves and other weathering traces can be observed on the surface of microplastics. The adhesion and growth of microorganisms are obviously observed on the surface of microplastics. Flavobacterium and Pseudomonas are commonly existed on the surface of microplastics of the two places. Besides, plenty of Limnohabitans and Rhodoferax are detected on the surface of microplastics in surface water, while the abundances of Arthrobacter, Massilia and Psychrobacter are higher in sediments.