Australia shares rise for 8th straight day

(Updates with opening levels)

MELBOURNE Jan 25 (Reuters) - Australian shares gained 0.4 percent in early trade on Friday, extending gains to an eighth straight session and touching a fresh 21-month high, boosted by solid China factory data and Japanese stimulus measures.

The benchmark S&P/ASX 200 index advanced 18.1 points to 4,828.3 at 2314 GMT, ahead of a holiday weekend. It was the best intraday level since May 2, 2011.

The index closed 0.5 percent higher on Thursday.

Australian markets will be closed on Monday for the Australia Day holiday.

New Zealand's benchmark NZX 50 index slipped 3.7 points to 4,186.2.

(Reporting by Victoria Thieberger; Editing by Richard Pullin)