The former Tottenham Hotspur winger has been discussing the current striker.
The 22-year-old netted - fortuitously - against Manchester City during a 4-1 win on Saturday afternoon and Waddle hopes that will get the ball rolling for the young England forward.
But he also feels it will be a 'massive achievement' to repeat the similarly massive achievement of last term, when Kane netted 31 goals for Spurs in all competitions.
Waddle is quoted as saying by the Mail: "Harry Kane is a young talent, scored a good goal on the weekend, but I think he's finding it a little bit harder this year because he's a marked man now after last year. Everything he hit last year went in and, let's be honest, this year they're not going in.
"He scored a good goal on Saturday - maybe that will start the ball rolling. But to get what he got last year, it would be a massive achievement, I've got to say, so we'll just see how he fares in the season."
The fact Kane is being man marked more often than not is certainly a key point worth emphasising. Even when the Tottenham striker scored against Manchester City at the weekend, he was let go because he was in an offside position.
More often than not, the 22-year-old will find himself being singled out in the Premier League.
For England, Kane was able to score with relative ease but against weaker back fours - San Marino goes without saying, while Switzerland are far from the solid team they were a couple of years back.
Hopefully, though, as Waddle says, the Manchester City goal will work as enough of a confidence booster for the Spurs hero to allow him to take on all of his newfound markers.