Mansoor was coming to Lahore from Islamabad on his car when it skidded off the road and overturned near Faizpur, a JuD statement said.
Mansoor died on the spot, while two others suffered serious injuries. They were shifted to a hospital in Lahore.
JuD chief Hafiz Saeed will lead Mansoor's funeral prayers at Township Lahore on Friday, the statement said. Mansoor was considered to be very close to Saeed.
Saeed and other JuD leaders have expressed their grief and sorrow and said that the JuD had been deprived of a 'great leader'.