Australian science is being left behind because of a lack of investment from government and industry, a group representing the nation's scientists says.

Government investment in new research is the lowest it has been in almost 20 years as a proportion of GDP, while private investment continues to fall, according to lobby group Science and Technology Australia.

At the same time, our science education system is deeply flawed at almost every level, the group says.

Leaders from almost 50 organisations representing the nation’s scientists met in Canberra on Tuesday to call for a national strategy for science.