By Friedrich Geiger 

BERLIN-- Volkswagen AG's net profit fell 16% in the second quarter because of weakness in China and restructuring charges at its trucks business, and the world's largest car maker by volume on Wednesday cut its full-year outlook for deliveries.

Net profit dropped to EUR2.67 billion ($2.95 billion), missing analysts' average forecast of EUR3 billion. Volkswagen now expects to deliver the same number of cars to customers this year as last year, after having earlier predicted a moderate increase.

"The difficult market environment and fierce competition, as well as interest-rate and exchange-rate volatility, and fluctuations in raw materials prices all pose challenges," said Chief Financial Officer Hans Dieter Pötsch.

Volkswagen shares declined on the news.

"Improvements in Europe [are] insufficient to ease investor concerns over broken China," said Evercore ISI analyst Arndt Ellinghorst.

Chinese joint ventures contributed about EUR1.1 billion to Volkswagen's operating profit, down from about EUR1.4 billion a year earlier, according to Wall Street Journal calculations based on first-half and first-quarter figures.

The company didn't disclose second-quarter figures for contributions from the joint ventures. Operating profit excluding those joint ventures rose 4.9% to EUR3.49 billion.

For the full year, Mr. Pötsch said he expects operating profit in China this year to be slightly lower than last year.

Revenue, which also doesn't include the Chinese joint ventures, increased 9.9% to EUR56.04 billion in the second quarter, helped by exchange-rate effects and a higher share of expensive vehicles among cars sold.

Volkswagen delivered 2.40 million passenger cars to customers in the second quarter, 2.8% less than a year earlier. A 9.5% decline in China, to 842,868 deliveries, outstripped gains in Europe and other regions.

The era of double-digit percentage growth rates in China is apparently over, said NordLB analyst Frank Schwope, but the country remains a promising market because car ownership is still much lower than in the West.

The German company overtook Toyota Motor Corp. as the car maker that sold the most cars in the world in the first half of the year.

Volkswagen's profit declined as it faces challenges on several fronts. The search for a new permanent supervisory board chairman continues after Ferdinand Piech quit in April. At the same time, the group is integrating its three truck brands, MAN, Scania and VW.

MAN booked EUR170 million in restructuring provisions in the quarter, which also dragged group earnings lower.

Volkswagen confirmed its forecast of a full-year operating profit margin of between 5.5% and 6.5% for the group, and 6.0% to 7.0% for the passenger cars business. These margin forecasts exclude Chinese joint ventures.

Mr. Pötsch, the CFO, said Volkswagen may announce restructuring measures in coming months.

"There is a lot of talk on the restructuring issue," he said regarding media reports. "I think if any changes need to be announced it is going to happen during the remainder of the year."

Write to Friedrich Geiger at friedrich.geiger@wsj.com

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