Gabriela Isler was crowned Saturday night in the pageant at a sprawling exhibition hall on Moscow's outskirts.
In the excitement just after the announcement, the tiara fell off Isler's head as she was being crowned by Miss Universe 2012, Olivia Culpo of the United States. Isler caught the crown laughing.
Patricia Rodrigues of Spain was the runner-up.
The panel of judges was led by American rock musician Steven Tyler.
Venezuelan President Nicolas Maduro congratulated Isler on Twitter, calling her title a "triumph" for Venezuela, a country that has now won three of the last six Miss Universe pageants.
In fact, Venezuela has won more major international beauty competitions than any other nation, and beauty pageants rank alongside baseball as the country's most-followed diversion, one that transcends social class and normally insurmountable political divisions.
A whole industry of grooming schools, plastic surgeons and beauty salons has emerged to prepare young women for the thousands of pageants that take place each year around the country in schools, army barracks and even prisons.
Venezuela has managed to keep its beauty queen industry flourishing, despite economic problems have worsened in recent weeks as inflation touched a two-decade high of 54 percent and shortages of basic goods like toiled paper and milk have worsened.
Driving the crisis has been a collapse in the currency, which has plunged to a tenth of its official value in illegal black market trading.
To arrest the fall, Maduro last week ordered the military to inspect prices and shut down businesses found to be charging abusive prices. A day after the government seized control of a nationwide chain of appliance stores, doors reopened Saturday to throngs of shoppers seeking to buy TVs, washing machines and refrigerators at a fraction of their listed price.