A toddler found on a street in western Sydney has been reunited with his mother.

Police say the woman contacted police about 8.30am (AEST) today after a public appeal was made to find the parents of the child, believed to be about 18 months old.

The little boy was discovered standing in Chapel Road at Bankstown near the intersection of Canterbury Road by a resident at about 4am (AEST).

The toddler was taken to Bankstown police station while police doorknocked homes in the area without success.

The toddler was described as having a fair complexion, with dark hair, blue eyes and a mullet-style haircut with shaved sides.

He was wearing dark blue pyjamas with spaceships on them and a nappy when he was found.

Police are still investigating how the child came to be on the street in the middle of the night.

AAP