The worst offender of all is Vietnam where an estimated 97 per cent of all software is unlicensed.
It was followed by other offenders including China where 94 per cent of software is illegal, Indonesia (89 per cent), Ukraine (89 per cent) and Russia (88 per cent).
According to the Business Software Alliance's (BSA) latest survey global software piracy grew from 37 percent in 2000 to 40 percent in 2001.
Said Robert Holleyman, president and CEO of BSA: "For the second year in a row, we have seen a rise in software piracy around the globe. This is an alarming trend despite our extensive efforts to enact laws and develop educational programmes that promote a safe and legal online.
This study reinforces the need to continue working aggressively to educate consumers and law enforcement agencies around the world that piracy is theft - plain and simple - theft that is robbing the global economy of hundreds of thousands of jobs and billions of dollars in wages and tax revenues," he said.
In the UK piracy rates fell one point to 25 per cent, bringing it level with the US.
But it still means that one in four of all software in use is illegal and the BSA in the UK has called on the European Union (EU) for tighter legislation to combat the problem.