From the 15,000 entries, the Grand Prize was awarded to a photograph titled The Power of Nature, showing Mexico's Colima Volcano erupting with lava as it is hit by a bolt of lighting.
The hand behind the shot, Mexican Sergio Tapiro Velasco, took the photograph from around 12 kilometres away.
Mr Velasco had photographed the volcano for more than a decade and had been tracking its activity closely in the month leading up to the shot.
Mr Velasco told National Geographic he heard a booming noise and saw the biggest volcanic lightning he had ever seen. But it was not until he looked at the photos he had taken that he realised what a spectacular event he had captured.
"When I looked on the camera display, all I could do was stare," Mr Velasco said.
"What I was watching was impossible to conceive, the image showed those amazing forces of nature interacting on a volcano, while the lightning brightened the whole scene.
"It's an impossible photograph and my once in a lifetime shot that shows the power of nature."
Mr Velasco was awarded a 10-day trip for two to the Galapagos Archipelago, as well as a $US2,500 prize.
In addition to the grand-prize winner, top photos were selected in each of three categories: Nature, People and Cities.
National Geographic, a science, exploration, and adventure magazine featured all of the winners and honourable mentions on its website.