Milaw powered away with less than three kilometres to go to complete the 42.195km in two hours seven minutes and five seconds, improving his previous best mark by 20 seconds on a cold and sunny morning.
Compatriot Asefa Mengistu was second 20 seconds behind, with Kenyan Lonyangata, winner of the past two editions, coming home third in 2:07:28.
In the women's race, Gelete Burka led an Ethiopian 1-2-3 when she clocked two hour 22:47 ahead of Azmera Gebru and Azmera Abreha, who finished five and 48 seconds behind, respectively.
"It was very very cold for me, it's difficult to breathe in these conditions but I'm very happy," said Burka.
Clemence Calvin, who was allowed to race after the Council of State, one of the country's highest courts, lifted her provisional suspension, took fourth place by beating the French record.
She clocked two hours 23:41.
Calvin, the European championships runner-up, had been provisionally suspended by the French Anti-Doping Agency after allegedly avoiding an out-of-competition control in Morocco.
She denied any wrongdoing and the Council of State on Friday allowed her to race.
(Reporting by Julien Pretot; Editing by Amlan Chakraborty)
