The race was the 43rd Belgian Grand Prix, the 31st to be held at Spa and the second since the circuit had been rebuilt and re-opened at half its original length in 1979.

Originally scheduled to take place on 2 June 1985, the Grand Prix was rescheduled for September after the recently resurfaced track became damaged during the race weekend.

Race organisers opted to resurface the track with a material called Stress Absorbing Membrane Interlayer that intended to provide improved grip in wet-weather conditions at a cost of £3 million.

Local bureaucracy and a harsh winter caused delays to the work, which were reportedly finished ten days before the event's scheduled date of 31 May, and forced a cancellation of a pre-race test session at the circuit.

[2] Warm weather, the powerful turbocharged cars of the time,[3] and their wide, slick tyres,[2] damaged the track during the Friday practice session.

[2] Discussions continued until 19:30 local time and drivers' representative Niki Lauda told the media that the Formula One race would be postponed.

"[3] The Belgian ASN was fined $10,000 and a provisional $100,000 bond to be deposited to FISA by the organisers would be returned in the event there were no further problems with the track on the rescheduled date.

During the buildup to the race FISA president Jean-Marie Balestre announced that the controversial South African Grand Prix would take place despite pressure to cancel the event as part of anti-apartheid embargoes.

X-rays revealed no break but Lauda was not fit to race so he returned home to Austria for further inspection and treatment from his physical therapist Willi Dungl.

Rain fell before the race leaving the grid to form on a damp track with wet-weather tyres for the first time since Senna won in Portugal.