Traditional method for seawater salinity measurement and electroconductivity measurement technology is introduced in this article. The merits,disadvantages,and measurement characteristics of the method are introduced. Recent developments in this field are discussed in detail,including microwave remote sensing,bare fiber sensor,surface plasmon resonance,position sensitive detector and optical technology,and salinity-sensitive material. Theory and current situation of these technologies are thoroughly analyzed. The advantage and disadvantage of each kind of salinity measurement technology are compared. In the end,some existed key problems which need to be solved in the future are proposed.