More than one in five foreign workers in Australia on a 457 visa are not being paid properly or doing the job they were brought here to do, according to the latest audit by the Fair Work Ombudsman.

Inspections by the Fair Work Ombudsman for July, August and September show concerns about salary and occupation at 107 out of 504 workplaces employing such visa holders covered by the audit.

Transport Workers Union national secretary Tony Sheldon. Credit:Janie Barrett

This amounts to concerns about 20 per cent of employers audited and is an increase from the 16 per cent of employers identified as not paying appropriate wages or providing proper jobs in previous audits between September 2013 and June this year.

Notable cases identified in the most recent audit include an overseas welder who is meant to receive $120,000 but is being paid $41,253 and a foreign electronic engineering technician working as a cleaner.