The Rajabhat University system may need to reduce social science majors, says Somwang Phithiyanuwat, an education scholar of the Royal Society.
The 170 Thai universities have more places than applicants, as students also turn away from courses like social sciences and turn towards science and technical classes.
They said new social trends could make some majors outdated.
The warning was raised by scho lars who noticed a significant decrease in the number of students and changes in the labour market that will potentially have a big impacton non-scientific programmes.
Many universities have begun to encounter problems in running some curricula as the courses are devoid of students, they said.
The worst-case scenario is some universities may be forced to shut down.
"Majors in the social science field are likely to go first," he told a forum.
"One reason is it cannot compete with the scientific area which students prefer."
Many women who receive a higher education tend to marry late and this can affect the fertility rate, or the average number of children born per woman, he said.
The National Economic and Social Development Board expects the number of Thais in the school-age group (0-21 years) will fall to 20% of the population in 2040, a sharpdrop from 62.3% in 1980.
The numbers are a wake-up call for university administrators to start thinking of changes in the number of students in each department, he said.
Thammasat University is also aware of the declining number of students and is finding ways to strike a balance as the university is now considered too big, said Thammasat University rector Somkit Lertpaithoon
The current social trend is making the university consider downsizing, or even closing, some social science majors.
Among them are the university's top degree programmes -- law and journalism andmass communication, he said.
"We'll gradually reduce the number of new law students from 500 to 400 and 300 a year," he said."