The Wall Street Journal reported that the move was a surprise and could have been prompted by Mollenkompf's position as a contender for the CEO position at Microsoft Corp.
Neither Mollenkompf, 44, nor Paul Jacobs, 51, the outgoing CEO and son of the company's founder, would comment on the Microsoft position, the newspaper said.
Mollenkompf, however, has been long assumed to be Qualcomm's next CEO, but an offer from Microsoft may have forced the issue, the Journal said.
Jacobs is to become the firm's executive chairman, when the management transitions occur in March.
"Obviously, our people are very talented and they are sought after. I just wanted to make sure that we ensured the continuity of the management team," Jacobs said.
"For me, Qualcomm is just this wonderful, wonderful group of people. I'm just really honored," said Mollenkompf, who will keep his title as president.