Japan's Nikkei 225 Stock Average surged 5.6 percent to close at a record 62,833.84 on optimism about a potential U.S.-Iran agreement.
The benchmark index finished above 62,000 for the first time in its history during trading on May 7.
The advance came as investors reacted to signs of progress in talks involving the United States and Iran.
Market participants pointed to reduced tensions in the Middle East as a key factor supporting risk appetite across Asian equities.