The Nikkei 225 index surged in Monday morning trading on the Tokyo Stock Exchange as strong economic data out of the US pushed up the dollar against the yen.
The Japanese currency fell to about a seven-week low.
The benchmark index rose more than 800 points at one stage as investors picked up export-related companies set to benefit from a weaker yen.
The currency traded at the 148-yen level against the dollar after weakening to 149 yen on Friday in New York.
Better-than-expected US job numbers on Friday prompted a wave of yen-selling in favor of the US currency.
The surprisingly strong US job market has cut into expectations that the Federal Reserve will announce a major cut in interest rates at its meeting in November. Employment figures are a key barometer for the Fed in judging the health of the US economy and setting its interest rate policy.