The 19-year-old, competing at a global event for the first time, finished 40th overall in a race dominated by African athletes.
The top 14 runners were all from the home continent. The race was won for a second year running by Ethiopia’s Letesenbet Gidey in 18 minutes and 34 seconds.
Her team-mate Hawi Feysa was second in 18:57 minutes, with Kenya’s world under-20 steeplechase champion Celliphine Chespol taking bronze in 19:02.
Weir was second European athlete home in 21:43. Second GB runner was Gillian Black in 46th position with a time of 21:59. Anna MacFadyen was 48th in 22:04, Phoebe Barker was 57th in 22:19 and Cari Hughes was 64th in 22:29.
The race was run in hot conditions and afterwards Weir said: “You train to be able to run hard, so in that aspect the course is fine because you’re used to running hard. But for me I hadn’t really adapted my training to the heat.
“I think if I was to do another course like this in these conditions I would definitely be changing aspects of my training as a means of preparation.”
Meanwhile, Weir’s City of Plymouth team-mate James Arnott continued his good early form in 2017 by winning 100m gold at the Sharjah International Open in 11.38 seconds.