Net income attributable to the company fell to $749 million, or 50 cents per share, in the second quarter ended March 31, from $1.16 billion, or 78 cents per share, a year earlier.
Revenue fell to $5.02 billion from $5.55 billion.
The quarter included a $974 million reduction to revenue, or 48 cents per share, related to the BlackBerry arbitration decision, Qualcomm said on Wednesday.
Qualcomm's patent-licensing practices have come under increasing scrutiny from governments across the world, as well as its key customers.
Qualcomm fired back at the iPhone maker last week, saying Apple had breached agreements with the firm.