The 26-year-old South Korea captain scored 25 times in 91 appearances for the French club during three seasons in Ligue 1.
The one-time Asian Young Footballer of the Year made his debut for the South Korea senior side at just 19, and played in both the 2006 and 2010 World Cups. He replaced the retired Ji Sung Park as captain of the national team earlier this year.
Arsenal manager Arsène Wenger said: “We are delighted to have signed Chu. He will add true quality to our attacking forces and will be a valuable addition to the squad.”
Chu Young Park said: "I am very honoured and I feel very happy to be at Arsenal. It is a dream to be here and I am really proud to be an Arsenal player. Now I just want to show how good I am and prove myself.
"In my opinion this is a great club, now I have to show what I can do on the pitch. I will do my best, I will never give up, I will show heart, I will give everything and I hope [the fans] will support me."
The deal is subject to the completion of formal registration processes.
Chu Young Park will wear the No 9 shirt at Arsenal. The striker prefers to be known as 'Ju' and will therefore have J. Y. Park as his shirt name.
