Shiv Sena MLA Tukaram Kate was attacked by a group of people, one of whom was wielding a sword, in the eastern suburb of Mankhurd late Friday night.
While Mr Kate escaped unhurt, one of his supporters suffered injuries fending off the attack, Shahaji Umap, Deputy Commissioner of Police, Zone VI said.
Mr Umap said that the incident happened when Anushakti Nagar MLA Kate, along with his bodyguards and supporters, was returning after participating in a Navratri celebration in the area.
A group of people attacked the MLA but his bodyguards and supporters managed to fend it off, Umap said.
A supporter of the MLA who was injured in the attack was rushed to hospital with doctors stating that he was presently out of danger, the official said.
The attackers fled the scene and efforts were underway to arrest them, he added.
Six persons of the group have been identified and the sword used in the attack has been recovered, he said.
A case under section 307 (attempt to murder) of the Indian Penal Code has been registered, he said.