INS Vajrabahu is an Indian Navy submarine base of the Western Naval Command located near Mumbai in Maharashtra. It was commissioned on 1 February 1996.
After the Indian Navy acquired the Vela class submarines in 1973 from the Soviet Union, the submarine base operated from temporary facilities in Mumbai. The facilities for the submarine base continued to expand over time. With the commissioning of the Shishumar class submarines, a submarine base complex was commissioned on 22 August 1987 by Adm RH Tahiliani in Mumbai for the submarine fleet of the Western Naval Command.
This operations base was expanded to include submarine support facilities and commissioned as INS Vajrabahu on 1 February 1996 by Admiral VS Shekhawat. In the ensuing years, a Submarine Motion Control Simulator, Attack Simulator and a water tower building were added to the base.
The base operates and maintains a sizable part of the Submarine Arm by providing material and logistic support to the Sindhughosh Class and Shishumar Class submarines based in Mumbai. It also has a non-dieted sick bay and handles preparation and maintenance of individual escape suits for submarine personnel.