Millwall square off against Spurs at White Hart Lane on Sunday and the Lions will surely have to be wary of former loan striker Kane, considering his wonderful run of form at the moment.
But Harris believes that in addition to Kane, his side will have to also worry about Tottenham's other talented attacking players as they can be just as devastating as the England international.
Harris told the EFL Weekly Podcast: "We expect the big guns to play, it's a competition that Tottenham are certainly looking to win.
"They certainly won't want to take any chances against us because of our previous results.
"Kane as an individual is difficult to stop, but it isn't just about stopping Kane, it's about stopping the supply to him and stopping Tottenham's strengths.
"If you do stop Kane, which is a difficult task, then there are three or four other individuals you have to worry about.
"Do we want to play a full strength Spurs side? In some ways, yes, because you are in the quarter-finals of the FA Cup and you want to pit yourself against the best.
"There's no doubt that if Spurs put out a full strength side and are at it, it could be a difficult afternoon for us and a difficult challenge but it is one we are looking forward to.
"If they underestimate us and weaken the side then maybe it gives more of a glimmer of an opportunity. Either way, whatever side Spurs put out, it will be an extremely talented side."