Rumen microbes ferment various feeds consumed by ruminants, producing volatile fatty acids that can be utilized by the host ruminants. Since 16S rRNA gene amplicon sequencing was developed, previously unculturable rumen microbes have been identified. Using this method, many studies on rumen microbiota in the field of ruminant nutrition have been conducted to expand our understanding of various factors that influence rumen microbiota such as diet, breeds, and regions. Because these factors impact the composition of rumen microbiota, understanding rumen microbiota in Korean native Hanwoo cattle is crucial for optimizing rumen fermentation and improving animal productivity. This review discusses recent 16S rRNA-based metagenomic studies on rumen microbiota, focusing on various factors including different rumen sampling methods, cannulation surgery, feeding systems, breed, and marbling score in Hanwoo cattle.