From 1976 to 1990, Sitthichai taught at King Mongkut's Institute of Technology Ladkrabang. He was the head of the Electronics Engineering Department from 1978 to 1982, associate dean of the Faculty of Engineering from 1982 to 1984, dean of the Faculty of Engineering from 1984 to 1988, and dean of the Faculty of Graduate Study from 1988 to 1990. During his time at KMITL, Sitthichai developed a rice moisture monitor based on electrical capacitance. At the time, General Surayud Chulanont was in charge of the army's rice promotion project, and the two men met. General Surayud had Sitthichai's device mass-produced and rice mills and markets were forced to buy it. Surayud's Minister of Science and Technology, Yongyuth Yutthawong, later noted that " never worked. It was like the taxis and hats. Every taxi driver was ordered to buy a hat, but they never wore it. The government forced everyone to buy these machines and they lay unused at the rice mills because nobody educated them about the system."
Sitthichai founded the Mahanakorn University of Technology in 1990 and became its first rector.
Open source software
A military junta headed by Generals Sonthi Boonratkalin and Surayud Chulanont overthrew the elected government of Thaksin Shinawatra on 19 September 2006. Surayud appointed Sitthichai, who he had previously known while working for the Army's rice project, as Minister of Information and Communication Technologies. ICT Minister Sitthichai became a vocal critic of open source software. In an interview, he noted, "With open source, there is no intellectual property. Anyone can use it and all your ideas become public domain. If nobody can make money from it, there will be no development and open source software quickly becomes outdated... As a programmer, if I can write good code, why should I give it away? Thailand can do good source code without open source."
Foreign technology
Sitthichai was a vocal opponent of foreign technology. In a speech at the Comworld 2007 fair at Siam Paragon shopping center, he said that it was wrong of Thai people to admire modern technology which was not developed by Thai people. "It is a fake development because the country is now getting worse as almost everything at the exhibition here is imported and nothing is made by Thais," he said.
Inventions
Sitthichai invented the meter used in Bangkok taxis. He also developed a euthanasia device that pumps carbon monoxide into a room.
Censorship
Sitthichai ordered a nationwide ban of the website YouTube on 4 April 2007. The reason for the ban was stated to be a distasteful video of King Bhumibol Adulyadej.
Hobbies
Sitthichai is an avid collector of firearms. He regularly carries a.45 caliber pistol.
