Equity, the actors and stage managers union which has 2000 members north of the border, said Northern Ireland and Wales were reaping the benefits of new studio investments with more repeat productions based there.
There are around 2,600 people employed in the wider film industry living in Scotland, around 8 per cent of the UK total, according to a 2014 Creative Scotland report.
Taggart, the long-running crime drama produced by STV, ended in 2010.
“Scotland is not as competitive as other parts of the UK in attracting films and telvision series to shoot here,” said Lorne Boswell of Equity.
“If you look at Wales, studio development has been underwritten by the BBC deciding to make it a production centre. Northern Ireland Screen has also proved itself dynamic at attracting investment,
“Unfortunately, Scotland is behind the curve.”
Plans for a national film studio to be built on green belt land near Edinburgh could cost £230 million and take five years to build, it was reported this week.
The project has yet to win backing from the Scottish Government or local authorities.
A separate scheme to build a studio near Cumbernauld is under consideration by Creative Scotland and Scottish Enterprise, but no start date has been set.
“Scotland is an attractive location for filming,” added Boswell. “But productions are having to find other places to do studio work and post-production.
“Say what you want about Taggart, but it provided an enormous amount of work for actors and those working behind the scenes.
“Scotland now lacks a returning drama that is broadcast across the UK.”
The situation is more positive for Scottish-based actors working in theatre, according to the vice-principal of one of the world’s leading universities for the performing arts.
Maggie Kinloch of the Royal Conservatoire of Scotland said 88 per cent of its drama and production graduates were either in employment or further education.
“Of course, not all of our graduates choose to remain in Scotland,” she said.
“But the National Theatre of Scotland is a huge factor. It employs a lot of our graduating actors, stage managers and technicians. It has raised the game and the profile for everyone.
“The days of actors having to move to London to have a career are gone.”