The video, shot on a cellphone by Armando Silva Salazar, shows the soldier's rifle becoming entangled in the Mexican flag and the soldier spinning wildly in the air before slamming into the ground.
According to Silva the unidentified soldier was lifted about 30 meters in the air.
He added that the soldier only suffered of a minor fracture to his ankle as well as concussion.
The 64-by-32-meter flag is the 8th largest in the world and it weights over 700 kilograms, local media reported. The ceremony on Friday 1st May was to commemorate May Day.