Thailand's ambition to develop a knowledge-based society and digital economy could hit a snag, as most of the workforce are only Mathayom 3 graduates or lower.
A report by the National Economic and Social Development Board (NESDB) said up to 65% of the 38-39 million workforce had graduated from Mathayom 3 or lower.
Only 23.2% of workers held vocational certificates or bachelor's degrees.
NESDB deputy secretary-general Chutinart Wongsuban yesterday said based on these figures, Thailand could expect to face difficulties developing into a digital economy.
"Half the country's workforce remains in the agricultural sector and independent occupations. Worse still, Thailand is becoming an ageing society," she said.
"This will inevitably affect the country's future development and economic growth."
The NESDB said Thailand now had an estimated 6.4 million elderly, accounting for 9% of the population.
In 2040, Thais aged over 60 are expected to number 20.5 million or 32% of the total population, with the total workforce seeing a drastic drop to 35.2 million from the current 39-40 million.
The shrinking workforce will inevitably affect the nation's future economic growth, agricultural, industrial and service sectors and may cause a heavy fiscal burden over the next 20 years, an earlier NESDB report said.
The agency warned the labour shortage was expected to become drastic this year, particularly once the government accelerated development of infrastructure projects and the digital economy.
An NESDB survey last year on labour demand by entrepreneurs showed demand for graduates of Mathayom 3 or lower was 79,814 jobs, with that for high schools at 27,827 and vocational schools at 47,608. Demand for holders of bachelor's degrees was put at 45,397.
The shortage of graduates of Mathayom 3 or lower was estimated at 52,400, with that for high-school graduates at 12,276.
The shortfall of holders of vocational certificates and bachelor's degrees was 22,085 and 15,162, respectively.
It was found that 49,575 graduates of secondary schools and lower levels were unemployed, with the number of unemployed high-school graduates amounting to 43,546.
The number of unemployed vocational-school graduates was 39,927, while the figure for those with a bachelor's degree was 89,627.
In a related development, the NESDB yesterday reported the unemployment rate was 0.84% of the total 38.6 million workforce, up from 0.73% in 2013 for a total 38.7 million workforce.