* Q2 net profit 3.38 bln riyals vs 2.91 bln riyals yr-ago

* Profits boosted by Finansbank acquisition

* Purchase helps raise net interest income

(Adds official Q2 figures, detail context)

By Tom Arnold

DUBAI, July 12 (Reuters) - The Gulf's largest lender, Qatar National Bank (QNB), reported a 16 percent rise in second-quarter net profit on Tuesday, broadly in line with analysts' forecasts and helped by its purchase of Turkey's Finansbank.

QNB, which is 50 percent owned by sovereign wealth fund Qatar Investment Authority, completed its 2.7 billion euro purchase of Finansbank from National Bank of Greece in June, helping cement its position as the largest lender in the Middle East and Africa by assets.

QNB's net profit totalled 3.38 billion riyals ($928 million) for the three months to June 30, up from 2.91 billion riyals in the corresponding period of 2015, according to its financial statement.

Three analysts polled by Reuters had on average forecast a quarterly net profit of 3.20 billion riyals.

For the first six months of 2016, the bank's net profit rose 12 percent from a year earlier to 6.2 billion riyals, it said.

Government spending on infrastructure and projects linked to the 2022 soccer World Cup has been a major source of credit growth in Qatar in recent years.

Still, banks are having to adjust to slimmer state spending this year after the government tightened its budget against a backdrop of lower oil prices.

The completion of the Finansbank acquisition helped boost QNB's net interest income to 5.61 billion riyals at June 30, up from 3.21 billion riyals a year earlier. Net income from fees and commission swelled to 1.27 billion riyals over the same period, compared to 582.16 million riyals a year ago.

Deposits at the lender stood at 488 billion riyals by June 30, up by 29 percent from the same point in 2015.

In a bid to strengthen the bank's capital adequacy ratio and support future growth, QNB last month raised 10 billion riyals of Tier 1 capital through a private placement of perpetual notes, the largest such issue ever conducted in the Middle East and Africa.

QNB's total capital adequacy ratio, a combination of both Tier 1 and 2 capital and a key indicator of the bank's health, stood at 14.2 percent as at June 30, above the 13.1 percent level QNB has to meet as part of its status as a domestically systemically important bank.

($1 = 3.6410 Qatar riyals)

(Editing by David French and Susan Fenton) ((Tom.Arnold@thomsonreuters.com; +97144536265; Reuters Messaging: tom.arnold.thomsonreuters.com@reuters.net))