A further 130 jobs are likely to go at RAF St Mawgan in Cornwall.
The relocation will be subject to union negotiations
The government has announced its intention to move support services for the fleet of Search and Rescue Sea King Helicopters to Portsmouth.
The job losses would form part of the government's review of military aircraft support.
The base at St Mawgan currently undertakes engineering support of the RAF's fleet of Search and Rescue Sea King helicopters.
Under the proposals announced by Armed Forces Minister Adam Ingram, service support would be moved to Fleetlands near Portsmouth.
The principal impact at RAF St Mawgan will be on service personnel and would result in the loss of around 90 service and 40 MoD civilian posts at the base.
Although it may be the government's preferred option, it is subject to 30 days of negotiation with trades union representatives.
The removal of the final flying squadron from the base was announced in July.
Mr Ingram has stressed that this latest announcement does not mean that RAF St Mawgan will close.
The future of the base will be considered in the Defence Airfield Review due to be completed sometime next year.