The PSNI is to launch a major recruitment drive this autumn.
Deputy Chief Constable Judith Gillespie said the campaign would target areas of the north-west, where some people were still reluctant to join the police.
Ms Gillespie told a meeting of the Northern Ireland Policing Board - which oversees the PSNI - she wanted the organisation be more representative of the ethnic and geographical make-up of the community.
She said: "We know we have an issue with recruiting police officers working in uniform and response in the Foyle area. We also know that's an issue in Strabane and to a lesser extent Omagh. Therefore it is quite legitimate for us to target our recruitment campaign towards that area which is under-represented."
In recent years dissident republicans operating in the north-west have stepped up their campaign of violence against the security forces.
In April 2011, Catholic PSNI recruit Ronan Kerr, 22, was killed when an undercar boobytrap device was detonated as he drove to work in Omagh.
Strand Road PSNI station in Londonderry has been repeatedly targeted - most recently in March, when police thwarted a rocket attack after intercepting a van carrying four primed mortars. In 2010 officers narrowly escaped injury when a car bomb exploded outside the station.
Dissidents were also behind several bombs left outside the offices of the UK City of Culture in Derry city centre.
The PSNI was forced to freeze recruitment over two years ago because of cuts to the policing budget but, with more than 1,000 officers due to reach retirement age over the next three years, trainee officers have to be recruited to retain the current quota of just over 7,000.
At present the PSNI is 30% Catholic. A controversial 50:50 recruitment policy imposed as part of the Patten policing reforms has now ended.