BEIJING (Reuters) - China's booming property market showed early signs of a softening in October after a fast and furious price rally that propped up economic growth this year.

A National Bureau of Statistics (NBS) survey out on Friday showed October's monthly price growth virtually halved to 1.1 percent from September's 2.1 percent, as most of China's first- and second-tier cities posted slowing price growth.

Analysts welcomed the softening as it showed that local and national measures intended to curb speculation were working without seeming to trigger a sharp price correction.

"October data showed the momentum is softening, and that is within market expectations," said Julia Wang, Greater China economist at HSBC global research said in Hong Kong.

"I think that's actually good news since it showed the effectiveness of the new curbs introduced earlier in October without depressing the market too much."

Despite the monthly slowdown, new house prices in China's 70 major cities still rose 12.3 percent in October from a year earlier, accelerating from an 11.2 percent increase in September.

Prices in Shenzhen, one of China's long-time high-growth markets, dropped 0.5 percent in October, the first fall since October 2014, suggesting restrictions to curb speculative buying in the hottest markets are starting to bite.

China has depended on a surging real estate market and government stimulus to drive growth this year, but fears of a property market crash have led more than 20 cities to introduce tightening measures to cool overheating markets.

HSBC's Wang said the impact of tightening measures on growth would be "limited" as the policies were still more relaxed than seen in previous tightening cycles, especially without a credit squeeze from monetary tightening.

"We expect monetary policy to remain loose next year," she said.

Wang estimated the property market currently contributed 17 percent of China's total investment, with infrastructure spending still the major driver.

Property investment rose in October on an annual basis to its highest since April 2014, according to Reuters calculations from data issued by NBS on Monday.

Analysts say the impact on real-estate investment from tightening measures is usually delayed, but a property market dampened by sluggish domestic demand could weigh on the economy from early next year, adding uncertainty to the growth outlook.

STRICT RULES TO CONTINUE

Sixty-five of the 70 cities tracked by NBS showed a year-on-year price gain, up from 64 in September. In the second-tier city of Hefei, once again the top price gainer, new home prices rose 48.4 percent in October, quickening from a 46.8 percent surge in September.

Analysts say a record headline figure in October suggests policymakers will maintain measures to bear down on price growth.

"The current strict policy tone will persist, which could add pressure to growth in the coming quarters," said Singapore-based Commerzbank economist Zhou Hao.

Some overheated cities are already beefing up existing measures with stricter multiple curbs, suggesting more cities may follow suit in bolstering controls.

On Tuesday, major cities such as Shenzhen and Wuhan stepped up restrictive measures with fresh curbs on borrowing and purchasing of multiple homes.

(Reporting by Yawen Chen and Nicholas Heath)