A 20-year-old man is facing indecent assault charges after allegedly approaching children through a fence at a childcare centre in Tasmania.

Staff took "immediate action" to ensure the safety of children and the man was removed from the area during the incident in the state's northwest on Wednesday afternoon.

Police say the man did not enter the yard of the centre, but made contact with children through a fence.

He was on Friday charged with three counts of indecent assault and was bailed to appear in Burnie Magistrates Court on May 16.

"All children and families involved have been provided with appropriate counselling and support," Tasmania Police said in a statement, adding it was an isolated incident.

"Investigations are continuing and the childcare centre is continuing to assist police with their inquiries."