Languages in AEC's members

The national integration of 10 countries in ASEAN including of Thailand, Myanmar, Laos, Cambodia, Vietnam, Malaysia, Singapore, Indonesia, Brunei, and Philippines. Each country has its own language as following table

Country	Official language	Minor official language	National language
Nation of Brunei, the Abode of Peace (Brunei Darussalam)	Malay	English and Chinese	Melayu Brunei (Brunei Malay)
Kingdom of Cambodia	Khmer	English, French, Vietnamese, Thai, and Chinese	Khmer
Republic of Indonesia	Indonesian		There are 742 different languages and dialects. Indonesian (form of Malay which is based on the prestige dialect of Malay)  is national language
The Lao People's Democratic Republic (Lao PDR)	Laos	French and English	Laos
Malaysia	Bahasa Malaysia	English and Chinese	Malay
Myanmar (Burma)	Burmese	-	Burmese
Philippines (Filipino)	Filipino and English	Spanish, Hokkien Chinese, and Teochew Chinese	Tagalog
Republic of Singapore	Malay	Mandarin Chinese	Singapore encourages people to speak two languages, English and Mandarin Chinese, for business and daily life.
Socialist Republic of Vietnam	Vietnamese	-	Vietnamese
Kingdom of Thailand	Thai	Laos, Northern Thai, and Southern Thai	Thai

Sources: http://en.wikipedia.org  and http://th.wikipedia.org