'The destruction of our planet continues at a pace we can no longer afford to ignore,' said the Titanic actor.
'We have a responsibility to innovate a future where the habitability of our planet does not come at the expense of those who inhabit it.
'I am proud to support these organizations who are working to solve humankind’s greatest challenge,' he said.
The millions in grants will support organizations including efforts to preserve the Earth's delicate ocean ecosystems and those working to protect the endangered gorillas in Virunga National Park in the Democratic Republic of Congo.
Conservation efforts to save the apes were the subject of last year's Oscar-nominated documentary Virunga, which DiCaprio executive produced.
