A Sydney man detained in China on suspicion of smuggling drugs has had his death penalty case pushed forward six months.

Peter Gardner, 25, was arrested last November in Guangzhou, where local police claim he tried to smuggle 40kg of methamphetamines out of China.

After several months in detention, Gardner will now face trial on May 7, News.com .au reports.

His lawyer, Craig Tuck, said the reason the trial has been brought forward is unknown.

Gardner could face death by firing squad if found guilty.

Peter Gardner was detained by customs officials in Guangzhou. (Supplied)

At least a dozen foreigners have been executed in China in the past 15 years, according to Amnesty International.

In China's legal system, once cases like Gardener's pass to the courts, conviction rates reportedly are 99 percent.

Gardner's travelling partner, Sydney woman Kalynda Davis, 22, was released without charge in December after a month in custody.

The pair apparently met on an online dating site, just weeks before the arrest, and arranged to travel to Guangzhou, in China's southern region, for three days.

The pair was on their way home on November 8 when they were stopped at airport security screening after checks revealed something unusual inside Gardner's bags.

Gardner's travelling partner, Sydney woman Kalynda Davis, 22, was released without charge in December after a month in custody. (Supplied) (Supplied)