The benchmark Nikkei 225 index at the Tokyo Stock Exchange gained 53.58 points to 9,007.88 by the break, while the Topix index of all first-section issues advanced 0.52 percent, or 3.90 points, to 747.17.
"Hopes for more Bank of Japan monetary easing will continue to support the market for the time being," Hiroichi Nishi, general manager of equities at SMBC Nikko Securities, told Dow Jones Newswires.
The Japanese central bank is widely expected to take further easing steps at a policy meeting next week in an effort to boost the economy and fight the stubborn deflation that has bedeviled Japan for years.
Tokyo's rise bucked a fall on Wall Street, where the Dow fell 0.19 percent on Wednesday as weak US corporate earnings dragged on sentiment.
The Fed said Wednesday it would stick to its $40 billion a month bond-buying programme -- known as quantitative easing -- for as long as needed and keep interest rates at record lows until least 2015.
In Tokyo trade, Sharp Corp. fell 4.79 percent to 159 yen after a report said the consumer electronics giant lost 400 billion yen ($5.0 billion) in the first six months of its fiscal year, nearly double its earlier projection.
Mobile operator KDDI surged 5.13 percent to 6,350 yen after saying it would merge its television operation with Sumitomo Corp's TV business.
Videogame giant Nintendo was off 0.77 percent at 10,210 yen after cutting its earnings outlook for the fiscal year to March by 70 percent on Wednesday.
A weaker yen helped some firms with overseas operations.
Toyota was up 0.8 percent to 3,120 yen, Toshiba gained 1.06 percent to 286 yen and Fast Retailing, operator of the Uniqlo cheap chic clothing chain, added 1.78 percent to 17,710 yen.
On currency markets, the euro bought $1.2987 and 103.84 yen compared with $1.2972 and 103.49 yen in New York late Wednesday.
The dollar was at 79.96 yen against 79.79 yen.