Dibaba, who broke world records at 1,500 metres and 3,000m earlier this year, clocked nine minutes, 00.48 seconds to smash compatriot Meseret Defar's mark of 9:06.26 set in 2009.
"I'm very delighted because to break three world records was what I'd planned and I'm very happy that has happened now," Dibaba told reporters after the two-mile, a distance that is not recognised by the International Association of Athletics Federations for record purposes.
"In the middle of the race I felt a bit weak and tired, but with the help of the crowd and all the buzzing I was able to gain momentum and get the record."
Britain's James Dasaolu sprinted to the year's fastest 60m, clocking 6.47 seconds in the preliminaries, appearing to injure his left hamstring during the final, which he won in 6.50.
"My left leg felt tight at about 40-50 metres. I think it's cramp, but I'll go and see the doctors and see what they say," Dasaolu, a medal hope for next month's world indoor championships, was quoted as saying by the BBC.
Ivorian world silver medallist Murielle Ahoure surprisingly edged Jamaican Olympic and world champion Shelly-Ann Fraser-Pryce in the women's race as both were timed in 7.10 seconds.
Olympic long jump champion Greg Rutherford, who ruptured a hamstring last year and failed to reach the world championships final in Moscow, was third in his first indoor event for four years with 8.00m, which equals his best ever leap indoors.