Based on systematic thinking, security soft threats are, in fact, systematic efforts of competing and hostile systems organized to disrupt all security infrastructures of our country. In this regard, disrupting the infrastructures which are intended to ensure the public security will appear itself as civil disorders that bring about instability in the national security of the country. The present study purpose is, to define a set of soft and hard lines of defense that as a smart and systematic confronting action can help police to provide safety and public security. Methodology of this research is based on analytical survey, some specific population in Tehran city that includes all universities, the clothes guild, the information and security police, the Iranian alliance of motion picture guild, the presses, all hospitals and other health centers through a survey analytically performed on 662 people randomly selected by two - stage clustering sampling. The library studies surveys, interviews, and researcher - made questioners are all instruments employed to gather required information and data. The validity of questioner is confirmed based on both senior experts’ points of view and principles and/or theories discussed in relevant literatures. This study presents a set of lines of defense which prevent a “potential soft threats” from turning into an “unpleasant public security catastrophe”. The arrangement of designed lines of defense is a critical point that may fix a set of lines defense which most likely operates effectively. In clearer, in operational environment, the softest lines of defense should be launched before the hardest ones. The situation in which the public security system is being threatened in a soft manner, the smart police force is expected to take soft and systematic approaches prior to the hard ones throughout the confronting process. Design of such lines of defense is just a part of soft confronting actions.