The Eight-time Olympic champion clocked 9.95 in his final Diamond League race to beat America’s Isiah Young (9.98) and South African Akani Simbine (10.02) while Britain’s CJ Ujah ran 10.02 to claim fourth.
The 30-year-old Jamaican has confirmed he will run the 100m and 4x100m relay at the World Championships in London in August, his final event before retiring.
With two weeks to go until the event, this was arguably Bolt’s toughest test since he won double Olympic gold at Rio 2016.
The global icon laboured to victory in 10.06 in Ostrava last month but finally dipped under the 10-second mark against a much tougher field in Monaco on Friday.
In his final race before London 2017, which takes place from 4-13 August, Bolt showed signs he could well bow out with yet another gold medal.