The annual event is usually held in May to mark the anniversary of the first conquest of Everest by Tenzing Norgay and Edmund Hillary on 29 May 1953.
More than 50 athletes ran in Monday's race from several countries.
Organisers said that the race showed Nepal was once again safe for tourists.
The devastating earthquakes in April and May this year killed nearly 9,000 Nepalis.
Eighteen climbers died on the slopes of Everest because of an avalanche triggered by the quake.
Head organiser Bikram Pandey told the BBC the "Run for Tourism Revival" showed that destinations in Nepal such as the Everest region are now ready and open for travellers.
The trail, known as the Tenzing-Hillary Everest Marathon, starts at Everest Base Camp - nearly 5,500m (18.050ft) above sea level where oxygen levels are low.
It is considered to be one of the world's toughest and most exciting trail runs.
The route goes past Buddhist monasteries and and across suspension bridges, plunging 2,000m (6.560ft) to the village of Namche Bazaar, known as the Sherpa capital.
At least $4,000 (Â£2,630) had been raised for post-quake reconstruction,  according to race organisers.
Fifty-four runners - half from Nepal and the rest from from countries including the UK, the US, Israel, Poland and Australia took part in the race which has taken place annually since 2003.
Race winner Bhim Bahadur Gurung told AFP that the high altitudes made the marathon "very difficult". Nepalis made up the first three to finish.
The air at base camp contains only 50% as much oxygen as at sea level, leaving many athletes struggling to breathe on even the smallest incline along 42km (26 miles) of vertiginous mountain paths.
1) Bhim Bahadur Gurung (4:01:54)
2) Surendra Basnet (4:03:18)
3) Pasang Lama (4:11:28)
Fastest foreigner: Andrew Leon Skidmore (4:15:20)
Runners have been taking part in the highest marathon in the world in the foothills of Mount Everest, four months after it was postponed because of Nepal's devastating earthquakes.