West Australian Police Commissioner Karl O'Callaghan has dismissed calls to increase the drinking age because he does not think it will stop young people abusing alcohol.

Australian of the Year Ita Buttrose said this week that a trial rise of the drinking age to 21 was worth exploring because she was alarmed by the number of children who ended up in hospital from alcohol abuse.

But Mr O'Callaghan said on Thursday he did not think it would work.

"I'm not supporting that change," he told Radio 6PR.

"We've got a whole range of things for 18-year-olds, so they can fight for our country, they can vote for the government of the day, and all of a sudden we're going to turn around and say 'but they can't drink'."