Young farmers play a significant role in sustaining food security and the communities’ and rural areas’ viability. However, as with many countries, Thailand is facing a decline in the number of young farmers who, if not productive and satisfied with their farm business, are likely to exit farming to take advantage of their increased educational level and off-farm job opportunities. Data were collected by interviewing young farmers in the Prachin Buri province, Thailand, with the aim of assessing their reason for farming in the long-term and the type of farming. Farming decisions can be categorised into three types: full-time profit-oriented farming with a focus on rice production (~53%), full-time multifunctional farming in innovative mixed or organic production systems (~23%), and part-time farming where young farmers work off-farm and farm outside regular working hours (~24%). Using path analysis, we investigated which physical and psychological factors affect young farmers’ decisions to pursue these three farming types. The results show that non-monetary farming’s benefits are as important as monetary benefits. Education, farming and regular off-farm work experience, farm production, market and pest problems, and government support directly affect the farming types. These effects were also mediated by attitudes towards farming and net farming income. Young farmers choosing to pursue multifunctional farming have higher incomes, more often apply sophisticated technologies, and farm more sustainably than those choosing the other types of farming. This indicates that a shift from conventional rice production to more diversified production systems using innovative technologies is needed to sustain farming success and retain young people in the farming sector.