Consumers in the U.S. frequently line up to pay $60 apiece for each year's installment of Activision Blizzard Inc.'s biggest franchise, "Call of Duty." But when the war-simulation shooting game reaches China's shores later this year, Activision will take a different tack: giving it away for free.

The Santa Monica, Calif., company is responding to the peculiarities of the fast-growing Chinese market, where game consoles barely have a presence and people typically gather in PC-laden Internet cafes to play free games that are...