In order to understand the occurrence and distribution of marine microplastics in the intertidal zone, a study on microplastics in sandy intertidal zone sediments was conducted on the south coast of Xiamen Bay in October 2022. The research results showed that the average abundance of marine microplastic is 2.43 items/cm2 in the sediment on the south coast of Xiamen Bay, the highest abundance occurred in the low tide region with 2.92 items/cm2, and the lowest abundance occurred in the high tide region with 1.73 items/cm2; the color composition of the microplastic were mainly white and black, including the highest abundance of white microplastics 1.50 items/cm2; The microplastics were mainly fibrous, flake and flocculent, and their abundance were 0.79 items/cm2, 0.76 items/cm2 and 0.56 items/cm2, respectively. In terms of particle size, the abundance of marine microplastics with 250 μm–425μm was 1.23 items/cm2, the abundance of those with a particle size of 425 μm ~ 830 μm was 0.69 items/cm2, and the abundance of those with a particle size of >830 μm was 0.50 items/cm2. The highest vertical abundance occurs in 0 ~ 2 cm with a value of 1.07 items/cm2.This study can enrich the background data on the distribution of marine microplastics in the intertidal zone of Xiamen Bay, and further provide scientific support for the monitoring and control of marine microplastics in the coastal areas of Fujian.