BANGKOK, Thailand – Japan remains Thailand’s largest accumulated foreign investor, with Japanese companies submitting more than 119 billion baht in investment applications in 2025. But the next test of the relationship is no longer simply whether existing factories stay. It is whether Thailand can move Japan’s established production network into new industries quickly enough.
Prime Minister Anutin Charnvirakul arrived in Tokyo with a meeting of the Thailand Team in Japan scheduled for September 21. The meeting is intended to hear concerns and proposals from Thai agencies in Japan and shape a more targeted approach to attracting Japanese businesses and investment, particularly in automotive manufacturing, supply-chain expansion and future industries.
The importance of Japan to Thailand is reflected in the numbers. Japan is Thailand’s third-largest trading partner, with total trade exceeding US$53.204 billion, equivalent to 7.77% of Thailand’s international trade.
Government data shows Japanese investment in Thailand reached 184.741 billion baht in 2025, with 248 Japanese projects approved for investment promotion worth 67.158 billion baht.
Separately, data from the Board of Investment (BOI) shows Japanese companies submitted 311 investment applications worth more than 119 billion baht during 2025, a 146% increase from the previous year.
The two figures should not be compared directly: 67.158 billion baht refers to projects that had received investment-promotion approval, while the 119-billion-baht figure covers applications submitted. Together, however, they point to the continuing weight of Japanese manufacturing and investment in Thailand. The bigger question is what role Japan sees Thailand playing beyond the traditional automotive industry.
Japanese manufacturers have spent decades building factories, parts suppliers, engineering capabilities, logistics networks and skilled labour in Thailand. Moving an entire production ecosystem is costly and complex. But the advantages built over the past decades do not automatically guarantee that the next generation of Japanese investment will come here.
A BOI survey of more than 520 Japanese companies released earlier this year found that 23% planned to increase investment in Thailand in 2026. Potential expansion extends beyond automotive manufacturing to electronics, chemicals, food, trading, finance and digital businesses.
For Thailand’s property and industrial sectors, that diversification could be significant. Investment expanding beyond established factories could create demand for industrial land, ready-built factories, warehouses and offices, as well as housing near employment centres. But the latest discussions should be seen as a starting point rather than evidence of new investment deals already secured.
For property investors, the important questions are where new projects will locate, how much electricity and water they will require, what types of workers they will need, and how closely they connect with ports, airports and existing supplier networks. Locations with vacant land alone may struggle to compete with areas that already have reliable infrastructure and established supplier ecosystems.
Thailand’s challenge is therefore not to build a new relationship with Japan, but to upgrade an existing one for the next era of global manufacturing. If Thailand can address permitting, energy, workforce skills and connections between Japanese investors and Thai suppliers, new investment could extend well beyond major factories to contractors, logistics operators, service businesses and surrounding communities.
The next signals to watch will be the outcomes of the Thailand Team meeting, projects that move from approval to actual investment, and the number of Japanese companies that follow through on expansion plans. The value of Thailand’s Japanese industrial base will ultimately be measured not by investment applications on paper, but by factories built, jobs created, technology transferred and new economic activity taking root. Thailand already possesses an industrial network that other countries would take years to build. The challenge now is turning that existing advantage into new industries, new technology and new economic growth.
