The maritime Silk Road steadily expanded with the enormous logistics, with the development of shipbuilding industry and sailing. Along with the technological improvement of navigation and ship manufacturing, maritime Silk Road had steadily been extended due to the massive quantity of goods being transported. Since Buddhism had been introduced to Northeast Asia, numbers of monks left for pilgrimage to India via Southeast Asia by sea. They returned with some materials, which will be offered to Buddha and other religious rituals. Monks were not the only group that used the maritime Silk Road. Many countries in Southeast Asia gathered various items for trade including Buddhist materials. Silk Road was a road exploited for trading both supplies and culture. The reason why Southeast Asia was regarded important in those times is that the supplies they own were evaluated significant and of high value. Moreover, unique natural objects and materials needed for spreading Buddhism and its rituals, such as sarira and aromatic trees that are directly related to Buddha’s divinity, were included in their supplies. Buddhism was initiated in India, but the trade of the sea road through Southeast Asia played an important role in spreading Buddhism through material. The divinity of the Buddha becomes visualized and materialized by the material itself, such as a sarira, or artifacts, such as ritual crafts. These materials contribute to spreading Buddhist cultures and popularizing Buddhism in that it inspires the believers’ belief and highlights the invisible divinity. Maritime Silk Road through Southeast Asia had not only been used as a trade route, but also assumed the role of culture transmission route.