Telstra is set to terminate 64 positions in Ballarat, with the telco saying the jobs are back-of-house roles in the regional Victorian city.
"These roles are not customer facing, and the proposed changes are designed to consolidate similar functions and remove duplication," a spokesperson told AAP on Wednesday.
Community and Public Sector Union organiser Teresa Davison said the news had shocked the Ballarat-based workers.
"This community already struggles with an unemployment rate of 7.7 per cent. We should be making sure that people can build lives and families here, not chasing opportunity out of town," she said.
Davison said Telstra gave assurances to the CPSU last year that it would train up workers for the types of jobs needed in the future.
"There are hundreds of new jobs in Telstra, but most of them are in Sydney, Melbourne, and Brisbane. Workers know they might have to leave Ballarat and relocate their families if they want to find another role," she said.