A 57-year-old employee who was part of the council's "streetscene" department, which is responsible for refuse and recycling collections, street cleaning, grass cutting and highway maintenance, was diagnosed with HAVS in September 2015.
During its investigation, the Health and Safety Executive (HSE) found that the council had several policies dating back to 2004 to tackle the risk of HAVS, but had not put them into practice.
The HSE also found that the council did not address the issue of HAVS after an audit in February 2011 had identified its failure to assess the risk to employees from vibration.
After Wrexham County Borough Council introduced health surveillance for vibrating tool users, a further 11 diagnoses of HAVS or carpal tunnel syndrome were made.
It pleaded guilty to breaching s 2(1) of the Health and Safety at Work Act. At Flintshire Magistrates' Court, District Judge Gwyn Jones said the starting point for the fine was £400,000 but reduced it to £150,000 because of the council's guilty plea and "other factors", Daily Post North Wales reported. It was also ordered to pay £10,900 in costs.
After the hearing HSE inspector Mhairi Duffy said: "This employee now suffers from a long term, life changing illness. The council should have implemented the policy they devised following the audit in 2011."