Investors gained confidence from Wall Street's rise of more than 11 per cent overnight, and from European measures to support banks.
The Hang Seng index opened 5.1 per cent higher as trading started in Hong Kong but was 4 per cent higher a little later at 16,964.12. The main sub-index of mainland companies listed in the territory was 5.7 per cent higher at 8,546.60.
The Nikkei 225 average was trading 13 per cent higher as traders broke for lunch at 9,355.56 -- and the broader Topix index was 13.1 per cent higher at 951.05. The yen weakened by around 1 per cent as far as Y103.07 to the dollar, which helped exporters as it makes their goods more competitive abroad.