The latest reading follows a 5.7 percent increase booked in November.
In the October-December period, core private-sector machinery orders logged a 0.1 percent quarterly drop, the Cabinet Office said, less than the 3.5 percent drop for the period previously projected.
Machinery orders are a key advance indicator for corporate capital spending and the government uses the data to predict the strength of business spending in a six to nine month period ahead.
Such business investment accounts for roughly 15 percent of Japan's gross domestic product.
Types of machinery included in the monthly government survey comprise engines and turbines, heavy electrical machinery, electronic and communication equipment, industrial machinery, machine tools, railway rolling stock, road vehicles, aircraft, ships, water crafts, as well as sub types in those categories.