Kane scored 73 goals for club and country last season. He won the Bundesliga with Bayern Munich and played his part in England finishing third in the World Cup.
Lamine Yamal appears to be Kane's main competition for the Ballon d'Or, with Kylian Mbappe also potentially in the running.
This year's award has sparked significant debate and figures across the sport have come out to effectively campaign for their preferred candidate.
Speaking after both he and Kane scored in Arsenal's 2-2 draw with Bayern Munich, Rice threw his support behind his international team-mate.
"For me, he's the clear winner," Rice said. "His numbers speak for themselves. The year he's had has been remarkable.
"He's obviously up against some other world-class players but when you play with him, you realise how good he is - and when you play against him, you see how much of a pain it is.
"For a striker to play that pass for their first goal then take the penalty how he did... he's ridiculous, he's such a good player."
Mutual respect: Harry Kane and Declan Rice
Getty
Kane opened Arsenal up with a perfect through ball for Alphonso Davies to equalise in the Champions League clash, before scoring himself from the penalty spot.
Rice ensured Arsenal left Munich with a point, though, as he combined with Viktor Gyokeres and finished past Manuel Neuer to make it 2-2.
"It was a great spectacle but we feel we could probably have had more," Rice said.
"Manuel Neuer's made some great saves, but so did David (Raya).
"The manager has drilled into us for the last two days we're not just coming in to sit and hit on the counter - we wanted to match them all over the pitch.
"At home, they're one of the best teams in Europe with Paris. On to the next one and we keep going."