Learner drivers in the Western Isles are forced to wait over 14 weeks before they can take their test.
Lengthy delays are affecting car and motorcycle theory tests.
Vocational tests for goods vehicles are also hard to held back.
Some people try to get round problem by travelling to the mainland for an earlier test, losing a day’s wage to take time off work.
MP Angus Macneil said the Driver and Vehicle Standards Agency (DVSA) must address the situation “as a matter of urgency.”
Mr MacNeil said: “I am aware that there are job opportunities in the construction and haulage industry but people are being held back from taking these jobs because of the delay at the DVSA. This is unacceptable.”
He added: “In the past, those wishing to take the theory test could expect to do so within a month.
“I fail to understand why there is such a lengthy delay when the theory test facilities are in place in Stornoway.
“I have been in contact with the DVSA and I am waiting for their response.”
14 week delay for driving tests
3 April 2017