The Post Primary Teachers Association says the Government is spending $200 million a year on ineffective teacher training.
The union surveyed teachers and principals, many of whom said that recent restructuring meant that getting the right training had become more difficult.
Association president Angela Roberts said contracts for supplying training are now shorter so there's no ongoing mentoring between trainers and teachers.
She also said the training providers are now based in limited areas, so some teachers don't have access to as much training as they might need.
Ms Roberts also said schools in areas away from cities miss out on professional learning and development.
The Ministry of Education said it's committed to making sure teachers have access to high quality professional development and targets resources to where they're most needed.
More on the quality of teacher training can be heard on Outspoken on Sunday.