Giles, who was a member of the successful Leeds side in the 1960's and 1970's, believes Reds boss Jurgen Klopp could spoil Van Dijk.
"I fear Van Dijk could be badly coached at Liverpool," Giles told Newstalk's Off The Ball.
"What worries me about Van Dijk is whether Klopp will have him playing in dead ball positions that wouldn't be correct.
"Klopp feels Van Dijk can solve some of their defensive errors, but I have my doubts that he will be properly used. I see other defenders there badly coach, with Klopp in charge of it.
"I watched Liverpool against Spurs a few weeks ago when they were well beaten and on the first goal, they were badly lined up. That comes from the coaches and Klopp, so Van Dijk would have been in that position if he was playing that day.
"The same faults happen time after time with Liverpool and that suggests they are being badly coached. When Van Dijk comes in, is he going to get badly coached? That would concern me. I have my doubts about it."