Google co-founder Larry Page is to become chief executive of the US internet search giant in April.
He will take over from Eric Schmidt, who has been in the job for a decade and will become executive chairman.
Google said Mr Schmidt would focus on "deals, partnerships, customers and broader business relationships".
The surprise news came as Google unveiled strong net profits in the last three months of $2.54bn (£1.6bn) on revenues of $8.44bn.
Mr Page, 37, is reclaiming the job he relinquished to Mr Schmidt, 55, when investors called for a more experienced business leade