Most of the Asian stocks gained Wednesday with investor sentiment turning positive as a rise in the U.S. industrial production indicated an improvement in manufacturing output in the world’s largest economy.

Japan's Nikkei Stock Average was up 1.33 percent or 115.57 points to 8816.88. Among major gainers were Unitika Ltd (5.71 percent), Oji Holdings Corp (4.50 percent) and COMSYS Holdings Corp (4.08 percent).

The Chinese Shanghai Composite fell 0.16 percent or 3.39 points to 2095.41. Hong Kong's Hang Seng was up 0.69 percent or 145.81 points to 21352.88. Among major gainers were Sands China Ltd (1.61 percent) and COSCO Pacific Ltd (3.27 percent).

South Korea’s KOSPI Composite Index rose 0.81 percent or 15.63 points to 1957.17. Shares of Samsung Electronics Co Ltd gained 0.08 percent, and shares of Hyundai Motor Co advanced 0.44 percent.

India's BSE Sensex gained 0.61 percent or 114.25 points to 18691.95. Among the major gainers were Wipro Ltd (0.82 percent), HCL Technologies (1.84 percent) and Punjab National Bank (2.83 percent).

Market confidence went up on the U.S. Federal Reserve’s Industrial Production and Capacity Utilization report Tuesday showing an upswing in the manufacturing output. The report, measuring the change in the total inflation-adjusted value of output produced by manufacturers, mines and utilities, rose 0.4 percent in September up from 1.2 percent fall in August.

However, analysts sense that the market optimism could quickly fade as more clarity is needed on the improvement of manufacturing output.

“The manufacturing sector will continue to struggle over the next year, as the global economic slowdown hits exporters. Motor vehicle output fell by 2.5 percent m/m in September, following a 5.1 percent m/m drop in August,” Paul Ashworth, an economist at Capital Economics, said in a note.

Meanwhile, investor sentiment was reinforced after German Chancellor Angela Merkel said that Germany wanted Greece to stay in the euro zone. Merkel added, while talking to reporters in Berlin that the work was not finished, and there is a whole lot to do in the next weeks. This came as a positive step while the troika, of the International Monetary Fund, the European Central Bank and the European Commission, is finalizing a report of progress made by Greece in reducing its fiscal deficit.