Tarbei, who was the defending champion, clocked 3 minutes 50.15 seconds, to better his previous record. Another Kenyan Jonah Kipkemoi finished 7th while Stanley Cheruiyot was placed 11th.
The 25-year-old Tarbei triumphed in front of a huge crowd at the Olympic Stadium, sparking questions about whether he could run in the Olympics.
“I am still young and maybe I am still aiming high, aiming to the sky and if I fall down I fall from the clouds,” said Tarbei.
Ethiopian Wondiye Fikre Indelbu was Tarbei's rival in the race but could only manage silver.
David Korir had earlier won silver in the men’s 1,500 meters T13 category. Kenya is currently placed 34th together with Belgium, Hong Kong and Thailand, after collecting 2 Gold medals, 1 silver and 1 bronze.
On Monday, Samwel Mushai Kimani became the first man to dip under four minutes as he set a world record 3:58.37 in the 1500m - T11.
Mushai surprised the world when he ran under four minutes, a record that electrified the whole country as well as those attending the Paralympic Games in London.
Posted by Koome Kimonye