When Little later lined up for a more formal photo with him, Trudeau gave him a hard time about his selfie skills saying obviously the photo had not come out that well.
While Little might have mucked up his own selfie with Trudeau, he did at least manage a good photobomb of Australian Labor leader Bill Shorten's attempt.
Little said Trudeau was full of praise for New Zealand.
They shared a brief conversation during a luncheon. "I said g'day and I enjoyed his speech [on diversity and equality] and he said 'well, you guys led the way on a lot of this stuff.'"
Little spoke about Labour's work around the Future of Work during the summit.
Little said the US elections dominated many conversations on the sidelines.
"You talk to the Europeans and North Americans, there was a real fear of Donald Trump getting elected. We look at the US stuff in New Zealand and we are slightly bemused by it all but they are really fearful of Trump being elected."
Another big topic at the summit was how to respond to the anti-Muslim sentiment breaking out in Europe after terrorist attacks.
Otherwise, the conference was staple social democratic party fare - diversity, equality and concerns about globalisation.
Trudeau's success in Canada's election last year gave hope to other social democratic parties - although Trudeau's success is yet to rub off on them.
The Labour parties of Britain, Australia and New Zealand have all since lost elections or are struggling in the polls.
Others at the summit included New York Mayor Bill de Blasio and former British Labor MP David Miliband, now chief executive of the International Rescue Committee.
