The chief executive officer of Samsung Electronics Co. is stepping down in a surprise resignation after decades at the company, saying it needed new leadership following a bribery scandal that led to the imprisonment of its de facto chief.

Kwon Oh-hyun, who also serves as co-vice chairman, announced his retirement on Friday as the Suwon-based company reported record operating income of 14.5 trillion won ($12.8 billion) on booming demand for displays and memory chips. He said the company faces an "unprecedented crisis" despite the financial success.

Kwon had emerged as the public face of Samsung Electronics after Jay Y. Lee, grandson of the company's founder, was detained on corruption charges and then sentenced to five years in prison in August amid a scandal that brought down South Korea's president. While the latest financial results show Samsung's business units operating smoothly, that in itself may present risks for Kwon, said Park Ju-gun, who tracks corporate executives at CEOScore.