Government spending was projected at 2.73 trillion baht, about the same as this year's 2.72 trillion baht, Arkhom Termpittayapaisith told Reuters.
The cabinet approved the budget plan on Tuesday.
The military government has stepped up big investment projects in a bid to boost the economy, which is still struggling since the army seized power in May 2014 to end months of street protests, with exports and domestic demand sluggish.