The Swiss ace won seven titles in 2017 to Nadal's six, but still ended up finishing as the world number two behind the Spaniard, who ended the year as the top ranked men's singles player.
Nadal leads the head-to-head record between the two players – 23 to 15 – but has lost his last five matches to Federer, with four of them coming in 2017. All four were on hard courts and three were in the finals – the Australian Open, the Miami and the Shanghai Masters.
Henman believes Federer has an edge over Nadal on the synthetic courts and it has been the same throughout their long standing rivalry for over a decade. The 31-year-old's big advantage in the head-to-head is due to his dominance on clay, where he leads the 36-year-old 13-2.
Federer and Nadal will also have to contend with a rejuvenated Novak Djokovic and Andy Murray in 2018, as both the players make their comebacks from lengthy injury absence. The Serbian has a better head-to-head record against both the Swiss and the Spaniard and if he remains injury free, he could be amongst the challengers in Melbourne.
"It's a hard court, I'd go with Federer. That was definitely the case in 2017," Henman told the Express. "Federer's always been pretty comfortable [against Nadal on hard surfaces]."
"If you look at their head to head, it's 13-2 on clay and if you take that out of the equation and just look at their head to head on hard courts, grass courts and indoor courts then Federer is going to be in the lead.
"But to build up the confidence and momentum to beat him four or five times in a row because he didn't have to play on clay that certainly helps," he explained.
"Federer was asked 'what do you put your success against Nadal in 2017 down to' and he said 'well, not playing on clay'. If it's a hard court, I'd give Federer the edge but it will be very interesting to see where Murray and Djokovic are at."
However, Nadal's participation at the Australian Open continues to remain in doubt after he pulled out of both the Mubadala World Tennis Championships and the Brisbane International, which generally serve as preparatory tournaments for the first Grand Slam of the year.