Organizers of the airshow said in a short statement that exhibitors and visitors should not travel to the show due to "severe weather conditions."
The show's daily flying display by international aerobatic pilots was also grounded due to the rainfall.
Rain is unusual, but occurs periodically during cooler months in the United Arab Emirates.
Neighboring Saudi Arabia also experienced heavy rainfall this past week. Officials there say flooding has killed at least five people.
The Dubai Airshow, in its fifth day on Thursday, grabbed headlines earlier this week when U.S.-based Boeing announced orders of around $100 billion. Its European rival Airbus netted around $40 billion in orders.
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