The yen is at its weakest level against the US dollar in 4 years and 8 months.
The Japanese currency hovered in the upper-114 range on Wednesday in Tokyo.
Traders have been selling the yen for the dollar, as inflation concerns in the United States push up long-term interest rates.
Analysts say that dollar-buying picked up pace after Tuesday's reports of strong retail sales in America.
They say higher interest rates are raising expectations for better returns on dollar-denominated assets.
Japanese businesses that focus on exports benefit from a weaker yen, as their products are cheaper overseas. However, there is a downside, as importing oil and other raw materials costs more.
Prices for crude oil and natural gas have been soaring, adding to concerns that the yen's further depreciation could lead to even higher costs of gasoline and other energy sources. That could weigh on household finances, and dampen consumer spending.