This research is motivated by the important role of the Bryophyte plant the in environment. However, environmental changes can negatively affect the growth of Bryophyte plants in certain regions, particularly in the area of the Pangandaran natural site. There is an assumption that environmental changes such as differences in the acidity of the soil and humidity can affect the growth of Bryophyte and its population spread. This study aimed to discover the structure of the Bryophyte plant during the dry season in the Pangandaran natural site. A descriptive method was used in this study a such the research design including both a sampling method and a explorative method which was a survey. Furthemore the study was conducted on the entire Bryophyte population in the Pangandaran natural site. Samples of Bryophyte plants were only taken when they were attached to trees at least 1 m from ground level and had a diameter of at least 20 cm. Data retrieval of the research was conducted through surface area calculation using square plot and environmental climatic factor data collection. Data analysis of the research includes the identification of the types of Bryophyte found, the calculation of importance value index (IVI) as well as analyzing the influence of climatic factors, especially acidity and moisture levels, towards the growth of Bryophyte. The results show that there were four Bryophyte species, in which the Bryophyte which dominates the Pangandaran natural site is Mastigolejeunea sp. The highest importance value index (IVI) is found in Mastigolejeunea sp which is equal to 135.2%, and that the climatic factors, acidity and moisture, affect the growth and population spread of Bryophyte. Based on the results of this study, it can be concluded that the Bryophyte which dominates the Pangandaran natural site is Mastigolejeunea sp. and the climatic factors, acidity and moisture, affect the growth and population spread of Bryophyte.
