Confirmation is expected from both clubs that the South Korean has passed a medical and will return to his former side.
The 32-year-old has failed to make a significant impact since moving to Loftus Road from Manchester United last summer.
Having initially been named as QPR captain, he was then stripped of the armband after a series of niggling injuries and the appointment of Harry Redknapp as manager.
Park's first spell with PSV came in 2003 when he moved to Holland from J-League side Kyoto Purple Sanga, having impressing for South Korea at the 2002 World Cup as they reached the semi-finals.
He won the Eredivisie title in each of his two seasons in Eindhoven before moving to Manchester United, where he became the South Korean to play in the Premier League.
Park, who retired from international football in 2011, played in three World Cups and is one of eight South Koreans to have won 100 caps.
He didn't feature in QPR's opening game of the season, where they came from behind to register a 2-1 win over Sheffield Wednesday.