A man, claiming to be Pujari, called the hotelier on his mobile phone on February 15 and asked him to pay Rs 50 lakh, they said.
The caller threatened to harm the hotelier if he did not pay the money, police said.
The hotelier later filed a criminal complaint.
Based on the complaint, an offence has been registered with the Shivaji Nagar police station at Ambernath under IPC sections 387 (putting person in fear of death or of grievous hurt to commit extortion) and 507 (criminal intimidation by an anonymous communication), police said.