The food fight isn’t over for McDonald’s.

The world’s biggest fast-food chain raised investor hopes for a long-awaited turnaround on Thursday, reporting its first US sales increase in two years.

US sales for restaurants open more than a year were up 0.9 percent, while global sales were up 4 percent, sending the shares up 8.1 percent to $110.87 — an all-time high.

The boost was the result of higher prices, however, which helped offset a decline in customers.

The burger giant, based in Oak Brook, Ill., had 1.1 percent fewer customers in the third quarter than it did a year ago, according to Hedgeye Risk analyst Howard Penney.

The company declined to provide customer traffic results for the quarter. A year ago, the number of customers was down more than 5 percent.

“Things are getting a lot better at McDonald’s, but it doesn’t happen in one quarter,” Penney said.