Pseudotaxiphyllum pohliaecarpum (Hypnaceae) is a common moss in western Japan and widely distributed in East Asia. It frequently produces spores and propagules. The number of propagules is estimated to range 300-3000 per 1cm² of mat. Thus, a great number of diaspores can be produced. However, the dynamics of dispersal of bryophytes has been little studied, especially dispersal distance and frequency. We captured, cultivated and then sequenced DNA from aerial materials, such as rain drops and snow. As a result of DNA barcoding, 25 strains were identified, including P. pohliaecarpum. The cultured material indicated both long-distance and short-distance dispersal of diaspores originating from sources outside Japan. We evaluated genetic diversity within P. pohliaecarpum and its allied species in order to understand the relationship between diaspore dispersal and population structure. Among Japanese populations, collected mainly from western Japan, we detected no variation of the rbcL gene region, although the rps4 gene indicated some point mutations. The availability of genotype data to infer population structure is limited and analysis of populations using faster-evolving genes or SNPs is needed. Sequencing the whole chloroplast genome and searching for a suitable regions to analyze genetic diversity among populations of P. pohliaecarpum is currently being undertaken.