Authorities in Western Australian have stopped two Japanese men from attempting to smuggle 30 lizards out of the country.

The men were caught as they tried to fly out of the Perth International Airport after putting the lizards in their checked baggage.

It is estimated the reptiles could fetch up to $130,000 on the Asian black market.

Rick Dawson from the Department of Parks and Wildlife says the lizards were taken from all over the state.

"We believe that a lot were taken around the metropolitan area," he said.

"You can't pick up Australian wildlife so if you see someone picking it up then you should inform the department."

"They certainly got them from Rottnest Island because we've got the rare form there and there's a number of them taken from Shark Bay."

Jan Hill from Customs and Border Protections says her team has a variety of ways to block smuggling operations.

"The process is using our intelligence holdings we establish a pattern of behaviour then in concert with our colleagues in investigations we can then use our intelligence holdings to detect when these people are about to leave the country," she said.

"We can then intercept their luggage and the persons, and use a layered approach with the use of x-ray and physical examination and then with the assistance of colleagues from the Department of Parks and Wildlife to do the full examination."

Western Australia's Environment Minister Albert Jacob has praised the agencies for their work in catching the smugglers.

But Mr Jacob says that under the current State act, the men only face a maximum fine of $38,000 and he does not believe this is a big enough penalty.

"This highlights for us as a government the importance of bringing in our new biodiversity conservation legislation," Mr Jacob said.

"The penalties at this stage for most of these lizards are only $4,000 per incident yet this entire yield could have got those smugglers $130,000 and I think that highlights the importance of updating the Wildlife Conservation Act which is an old 1950 act, bringing it up to date and having modern penalties that fit the crime."

The men could also face penalties under a separate Commonwealth act.