BEIJING, Nov 1 (Reuters) - Growth in China's services industry cooled in October, an official survey showed on Sunday, suggesting pressures on the world's second-largest economy may be mounting despite a raft of stimulus measures.

The services sector has been the lone bright spot for the economy in the last few years, helping to offset a faltering factory sector, but it too has begun to show signs of fatigue in recent months as consumers grow more cautious.

The official non-manufacturing Purchasing Managers' Index(PMI) fell to 53.1, from September's 53.4, according to the National Bureau of Statistics(NBS).

The activity reading, while still robust, is the lowest since the depths of global financial crisis. A reading above 50 points indicates an expansion in activity on a monthly basis, while one below that points to a contraction.

The services sector has accounted for the bigger part of China's economic output for at least two years, with its share rising to 48.2 percent last year, compared with the 42.6 percent contribution from manufacturing and construction.

Data last week showed China's economy grew 6.9 percent between July and September from a year earlier, dipping below 7 percent for the first time since the global financial crisis, though some market watchers believe current growth is much weaker than government figures suggest.

(Reporting By Xiaoyi Shao and Nick Heath; Editing by Kim Coghill)