The Nikkei 225 Stock Average rose 0.30 per cent, or 25.73 points, to 8,667.58. The broader Topix Index advanced 0.53 per cent, or 3.89, to 733.67.
"There remains a significant risk that policy makers will keep intervening to support economic confidence and financial markets," said Mikio Kumada, a Singapore-based global strategist for LGT Capital Management.
"Overly bearish investors still risk being caught wrong-footed in rising markets. A reasonably constructive investment approach remains appropriate for now, with a slight tilt in favor of selected risky assets."