| Honorific-Prefix: | Field Marshal |
| Praphas Charusathien | |
| Native Name: | ประภาส จารุเสถียร |
| Native Name Lang: | th |
| Office: | Deputy Prime Minister of Thailand |
| Term Start: | 9 December 1963 |
| Term End: | 14 October 1973 |
| Primeminister: | Thanom Kittikachorn |
| Term Start1: | 1 January 1958 |
| Term End1: | 20 October 1958 |
| Primeminister1: | Thanom Kittikachorn |
| Office2: | Minister of Interior |
| Term Start2: | 19 December 1972 |
| Term End2: | 14 October 1973 |
| Successor2: | Kamol Wanprapa |
| Primeminister2: | Thanom Kittikachorn |
| Term Start3: | 23 September 1957 |
| Term End3: | 17 November 1971 |
| Predecessor3: | Phao Siyanon |
| Office4: | Commander-in-chief of the Royal Thai Army |
| Term Start4: | 1 October 1964 |
| Term End4: | 30 September 1973 |
| Predecessor4: | Thanom Kittikachorn |
| Successor4: | Kris Sivara |
| Office5: | Director-General of the Royal Thai Police |
| Term Start5: | 1 October 1972 |
| Term End5: | 16 October 1973 |
| Predecessor5: | Prasert Rujirawongse |
| Successor5: | Prajuab Suntarangkool |
| Birth Date: | 25 November 1912 |
| Birth Place: | Mak Khaeng, Udon, Siam (now Mueang Udon Thani, Udon Thani, Thailand) |
| Death Place: | Bangkok, Thailand |
| Spouse: | Sawai Charusathien |
| Children: | 6 |
| Signature: | Praphat Charusathian signature.svg |
| Allegiance: |  Thailand |
| Serviceyears: | 1933–1973 |
Praphas Charusathien (Thai: ประภาส จารุเสถียร,, in Thai pronounced as /pràʔpʰâːt t͡ɕaːrúʔsàʔtʰǐan/; 25 November 1912 – 18 August 1997) was a Thai military officer and politician. He was a field marshal of the Royal Thai Army and minister of interior in the governments of military rulers Sarit Thanarat and Thanom Kittikachorn.
Praphas graduated from the Chulachomklao Royal Military Academy and became an infantry officer. He was sponsored by Field Marshal and Prime Minister-to-be Sarit Thanarat. He was quickly promoted to higher ranks. In 1957, Sarit appointed him minister of interior, a position in which he continued to serve after Sarit's death in 1963. The new Prime Minister was Thanom Kittikachorn, whose son married Praphas' daughter. From 1963 to 1973, he was additionally deputy prime minister and Commander-in-Chief of the Royal Thai Army. During this time, Praphas was the strong man in the background who pulled the strings in the Thanom government. He was known for obscure financial transactions and political intrigues, while sitting on the boards of 44 companies.[1]
In 1973, he was replaced as army commander by Gen.Krit Srivara, which signaled his loss of influence. In October 1973 protests against the rigid military rule grew into a massive popular uprising that was answered by a bloody crackdown on the protesting students and democracy activists. The many dead civilians prompted King Bhumibol Adulyadej to intervene. Praphas, Thanom and his son-in-law Col.Narong Kittikachorn went into exile.
Praphas returned to Thailand in January 1977, after the military had ended the democratic interlude in October 1976. However, he was not able to exercise political influence again.
Praphas married to Thanpuying Sawai Jarusathien, daughter of Lt. Von and Huai Panprasit. They have a total of 6 children. Praphas's children were married to important people with military and political power, including Supaporn Charusathien married with Narong Kittikachorn son of Thanom Kittikachorn, Orapan Charusathien married with Yuthasak Sasiprapha and Supanapa Charusathien married with Somtat Attanand.
Praphas Charusathien died on 18 August 1997 in Bangkok.
received the following royal decorations in the Honours System of Thailand:
Netherlands :
Germany :
Malaysia :