"Matters pertaining to internal security came under discussion during the meeting," according to a statement by the PM office.
They also discussed steps for security of China Pakistan Economic Corridor (CPEC) project which runs through Pakistan- occupied Kashmir (PoK).
Sources privy to the meeting said that the situation in Karachi, tension with India and relations with Afghanistan were discussed.
The army chief also briefed Sharif about the latest situation on the Line of Control (LoC).
Government and security institutions are under pressure from opposition Pakistan People's Party (PPP) and Mutahidda Qaumi Movement (MQM) due to arrest of their senior leaders for corruption or having links with militant and criminal groups in Karachi.
The meeting was held after Interior Minister Nisar Ali Khan briefed the Prime Minister about his recent visit to Britain and meetings with the British leadership.