Abstract. Susilo F, Pasaribu N, Syamsuardi, Siregar ES. 2022. Diversity and distribution of liverworts in Mount Sibuatan, North Sumatra, Indonesia. Biodiversitas 23: 4539-4548. Due to a lack of research and publication, information about the presence of liverworts in North Sumatra and the island of Sumatra is still lacking. Therefore, Sumatran liverworts, especially in North Sumatra, are less well known than those in Java and other areas of Malesia. This research was conducted at Mount Sibuatan, North Sumatra, to analyze the diversity and distribution of liverwort species in this area. A survey along the hiking trail from an altitude of 1500 m to 2500 m was used as the collection method. Sampling was conducted at 60 points on the hiking trail, 100 meters from each end. Eighty-three species of liverworts were recorded from Mount Sibuatan, belonging to 23 genera and eight families. Two species were new records for Sumatra, namely Drepanolejeunea pentadactyla and Radula verrucosa. The largest family was Lejeuneaceae (12 genera and 26 species), contributing to 31% of the total species. Another dominant species from the collection was Bazzania tridens, with 121 individuals. Mount Sibuatan Liverworts were found on various substrates, and most of them grew on trunks or branches of trees, the ground, rotting logs, and living leaves. The liverworts were distributed from altitudes of 1531 to 2454 m. Twenty-eight species were identified in various elevations, from lower to upper montane forests. Furthermore, fifty-four species were confined to the lower montane forest (1200-2100 m), and one was restricted to the upper montane forest (2100-3000 m). The findings revealed that the montane forest of Mount Sibuatan is teeming with hitherto unknown liverworts.