Speech Pathology Australia chief executive Gail Mulcair said Launceston General Hospital, St Giles Therapy Services and the Health Department's child development unit were all understaffed.

Ms Mulcair said the shortage was made worse by poor coordination among providers and recruitment difficulties in Northern Tasmania.

She said some children faced waiting lists of many months to see a speech pathologist.

And she said recent research showed an alarmingly high (41 per cent) prevalence of prep-aged children in the North with speech and language impairments.

"Tasmanian parents are frustrated and concerned that their children are missing out on vital speech pathology services due to staff shortages causing long waiting lists," she said.

"Because speech problems are not classed as life-threatening, they can often be placed at the bottom of the barrel."

St Giles allied health general manager Catherine Merry the charity had funding for two speech therapists working with children having speech difficulties, which was separate to programs helping children with multiple health difficulties.

She said the one therapist recruited for the program had finished and St Giles was waiting for a Federal Government decision on funding after June 30.

Bass Labor MHR Jodie Campbell could not be contacted for comment.

Health Department principal allied health advisor Lee McGovern said an initiative called the children's therapy improvement project would involve some reconfiguration of services but there had been no reduction in speech pathology positions in the North.

"The level of demand for speech pathology in the North is higher than the national average and this has placed significant pressure on services," she said.

Ms McGovern said the therapy improvement program aimed to ensure children with complex therapy needs received coordinated, timely and appropriate allied health services.