Today, microplastic pollution has drawn global attention. Although many studies have recently been conducted on this topic, the majority of them have focused primarily on marine environments. To better understand the distribution of microplastics, remote regions must also be investigated. Rainfall collection is an appropriate method to assess potential atmospheric microplastic contamination. However, methodological clarity regarding microplastic identification remains limited. This study aimed to quantify fiber microplastics in rainfall samples collected from Valle d’Aosta, Italy. Samples were carefully collected and stored in glass containers to avoid contamination. Following sample preparation and filtration, particles were scanned using digital microscopy. Subsequently, particle confirmation was performed using Raman spectroscopy.