Third demography, Laos has a population of around 6.5 million Lao nationality khma and hmong official language of Laos, the Lao language. Vientiane is the embodiment of the Lao population. Religion is Buddhism. Cambodia has a population of about 15 million citizens, Cambodia, China, Vietnam and khmer khmer official language is the embodiment of the phnom penh religion is Buddhism, Islam and Christianity.citizens