Cambodia, (Kampuchea) is land of Buddhism. Cambodians ethnically and historically known as the Khmers. It covers the bottom of the Indochinese peninsula, having an area of 181, 0355 sq kms. Cambodia comparatively is a small country of South-East Asia, Cambodia has a population of 16 million, (16,133,484) of which the Khmers who comprise 94 percent from the majority. The other sizable ethnic groups are of Vietnamese and Chinese origins. According to the Samantapasadika, the commentary on Vinaya Pitaka, and a Sri Lankan chronicle Mahavamsa, after the third Buddhist Council which was held at Pataliputra (Modern Patna), India, in the third century B.C., under the presidentship of Thera Mahamoggaliputta Tissa, and was patronized by emperor Dhammasoka, sent a Buddhist mission headed by two monks, namely Sona and Uttara from Jambudipa (India) to Suvarnabhumi in order to propagate the Buddha’s teachings there. In ancient times Suvarnabhumi covered a large part of South-East Asia including Cambodia. Suvannabhumi covered modern Myanmar, Thailand, Cambodia, Laos, Vietnam, Malaysia, and some parts of Indonesia. Ancient inscriptions and various historical documents explain that in Cambodia Buddhism has existed in the country since the third century B.C., although practice of Buddhism (Mahayana and Theravada) changed according to the faith of the king. This paper is covering the Historical, Political and Social impact of Buddhism in Cambodia. This paper explains the introduction and growth of Buddhism in Cambodia.