Klinsmann had a successful career as a striker for clubs such as Inter Milan, Tottenham and Bayern Munich, but some South Korean fans have questioned his record as a coach.
"Jurgen Klinsmann is a strong personality," Michael Muller, a Korea Football Association official who oversaw the selection process, told a news conference.
"From the first second (of the interview) it was clear he wanted the job. He was focused, motivated and he was interested. He wants success."
Klinsmann took charge of Germany in 2004 and led them to third place in the 2006 World Cup on home soil, losing to eventual winners Italy in the semi-finals.
In 2011 he was appointed head coach of the United States, but was sacked in 2016 after two World Cup qualifying defeats.
His most recent coaching position, in 2019-20, lasted only 10 weeks at Bundesliga side Hertha Berlin.
The 58-year-old succeeds Paulo Bento, who took South Korea to the last 16 of the World Cup in Qatar, where they were beaten 4-1 by Brazil.
Muller defended his fellow German's track record.
"Football is not only tactics. Football is individuality. It's about teamwork, how to motivate your team in special situations," Muller said.
"Jurgen Klinsmann absolutely has tactical abilities."
Klinsmann signed a three-year contract and will arrive in Seoul next week.
His first match will be a friendly against Colombia on March 24.
