UBS Group has named the head of ING, Ralph Hamers, as the successor to Sergio Ermotti, the Swiss bank’s chief executive.

In a surprise announcement late on Wednesday, UBS said Mr. Hamers would leave Netherlands-based ING in June after a 29-year career to join UBS, the world’s biggest wealth manager, in September.

Mr. Ermotti has spent close to a decade at UBS, winning plaudits for overhauling its strategy after the financial crisis, cutting its investment bank and growing its wealth management business.

But UBS missed its profit and cost targets for 2019 amid ultralow interest rates in Europe and increased competition from U.S. rivals, forcing Mr. Ermotti to dial back some of its goals. UBS shares fell sharply last year, and the company was hit by a 4.5 billion euro ($5 billion) fine in a French tax fraud case.