Chinese counterfeiters have diversified from fake designer handbags to fruit, trying to pass off Chinese grown produce as Australian.

Citrus Australia says the fraudsters are trying to cash in on high prices and rapidly growing demand, with about 18,000 tonnes of mandarins and oranges exported to China last year.

Andrew Harty from Citrus Australia said spelling mistakes on labels and out-of-season availability make the falsified fruit stand out from the genuine article.

"What is particularly alarming to us is where we see fruit that has been dipped in a dye and we know these dyes are quite toxic," he told Radio National Breakfast.

"The colour is incredibly artificial, so it will be this glowingly deep orangey red colour."

Mr Harty said another common sign of the counterfeits is that they often only dye the top layer of fruit in a box.

The counterfeit fruit is being sold at wholesale markets in China and also in other Asian markets.

Sorry, this audio has expired Chinese fruit fraud

Mr Harty said China is a lucrative market, and Australian exports have grown rapidly over recent years.

"Because we've got product that's got a reputation for being sweet, safe and healthy, and also because that's in high demand in China and attracts very high prices there, obviously it's something of value that's worth faking," he added.