The prices of goods traded between companies increased for the fifth straight month and sharp year-on-year rises have shown in recent months -- 5.0 percent in June and 5.1 percent in May. The latest number revealed the steepest gain since September 2008, according to the central bank.
A weaker yen also led to higher raw material costs for companies, the data showed. Import prices jumped 27.9 percent while export prices gained 11.2 percent, both in yen terms.
Wholesale prices' effect on consumer prices is commonly delayed. The BOJ is struggling to achieve its inflation target of 2 percent, measured in consumer prices, while its peers in the United States and Europe are carefully monitoring rapid inflation.
The newest survey revealed that petroleum and coal product prices jumped 38.8 percent from the earlier year, tracking higher crude oil prices. The pace of rising declined from a 42.0 percent gain in June.
Prices for wood and lumber products soared 33.1 percent on supply shortages due to increasing demand for house building and other uses.
Nonferrous metal prices rose 32.3 percent while those for scrap and waste surged 81.2 percent. Prices of textile products, often indicating the strength of domestic demand, went up 0.5 percent.
"The global economic recovery continues in line with progress in vaccinations (against COVID-19) and wholesale prices are facing upward pressure," a BOJ official said. "But coronavirus cases have been resurging at home and abroad, and uncertainty is rather increasing."