Lukashenko, who has ruled the eastern European country since 1994, has called fears over the coronavirus a "psychosis" and variously suggested drinking vodka, visiting saunas or playing ice hockey to beat the disease.
Spectators in stands in the capital Minsk, a few of whom wore masks, looked on as soldiers marched, tanks rolled past and Su-30 fighter jets flew in formation overhead.
Lukashenko's insistence on going ahead with the display contrasted with neighbor Russia, which scaled back celebrations amid a jump in coronavirus cases and postponed its usual massive military parade on Red Square.
Dressed in military uniform and surrounded by generals, Lukashenko said it was unacceptable for Belarus to even think about canceling the parade.
"There will be people who will condemn us," Lukashenko said. He told such critics: "do not rush to draw conclusions, let alone condemn us, the heirs of the Victory, the Belarusians ... We simply could not асt differently, we had no other choice."
Belarus has not imposed lockdown measures or social distancing rules, and kept its borders open while countries around the world have closed them.
"This is a demonstration of determination, will, strength, not so much for society as for the inner circle of the elite," said Andrey Egorov, senior analyst at the Center for European Transformation. "It's a demonstration that everything remains under control."
Another reason for staging the parade could be an act of one-upmanship against Russian President Vladimir Putin. Ties between the two traditional allies have been strained, especially over Moscow's decision to scale back subsidies and loans that prop up Lukashenko's rule.
"Against the background of Putin's canceled parade, Lukashenko has the opportunity to draw attention to himself," said political analyst Alexander Klaskovsky.
"This is such a kind of revenge for the numerous humiliations. Putin hid in the bunker, and Lukashenko at that time will be standing on the podium in a beautiful uniform.”
The World Organisation has called on Belarus to introduce tougher measures to fight the coronavirus and the head of its Minsk office has expressed concern about holding the parade.
There are 21,107 confirmed coronavirus cases in Belarus, with 121 deaths. But some in the country believe the official statistics underestimate the true toll.