UPDATE 1-China's CITIC Securities reports biggest H1 profit growth in 3 years

* CITIC Securities reports fastest H1 profit growth in 3 years

* H1 net profit at 6.45 bln yuan vs 5.57 bln yuan a year ago

* Performance down to stable flow of IPOs (Adds details)

SHANGHAI/BEIJING, Aug 22 (Reuters) - China’s biggest brokerage, CITIC Securities Co reported a 15.8% rise in first-half 2019 profit on Thursday, the biggest rise since 2015, on a steady flow of public listings.

Net profit for the six months ended June rose to 6.45 billion yuan ($911 million) from 5.57 billion yuan a year ago, largely in line with the preliminary results released in July.

Brokers in China have revived since a stock market boom came to a turbulent end in 2015.

The upbeat performance is down to a steady flow of public listing approvals and expanded client base, the brokerage said in a statement posted on the Shanghai stock exchange.

The country’s mixed-ownership reforms have increased the number of merger and acquisition deals which has also benefited the firm, it added.

In the second half of this year, the tech share rally on the new Nasdaq-like STAR board will give brokers a new source of revenue, which will lift large brokerage firms such as CITIC, analysts said.

Equities investment returns, the biggest growth sector for the firm, grew 24.76% on year to 5.92 billion yuan by end-June, versus 4.74 billion yuan in the same period a year ago.

In Shanghai, CITIC closed down 0.31% at 22.71 yuan on Thursday. Its Hong Kong shares closed down 0.14% at HK$14.42.

China’s blue-chip CSI300 share index has jumped 26% this year, and the benchmark Shanghai Composite Index increased by 15.63% this year, Refinitive data showed.

CITIC’s net profit surged 58% in the first quarter of 2018, it reported in April. < nL3N21S2FQ> ($1 = 7.0834 Chinese yuan renminbi) (Reporting by Cheng Leng in BEIJING and Engen Tham in SHANGHAI; editing by Christian Schmollinger and David Evans)