Polydiacetylene(PDA)-based sensors possess a number of properties that can be successfully applied for label-free detection system. PDA is one of the most attractive color-generating materials, with growing applications as sensors. Here we introduce various PDA-based devices, used as biosensor, chemosensor, thermosensor, and optoelectronics sensor. In general, PDA liposomes and films are closely packed and properly designed for polymerization via 1,4-addition reaction to form an ene-yne alternating polymer chain. PDA-based two/three dimensional structure have been used for colorimetric or fluorescent devieces, sensing biological as well as chemical components. This color-generating material also present a very high charge carrier mobility, allowing its application as field-effect transistor(FET). The immobilized PDA structures or films have distinct advantages for the detection of low concentration target molecules over the aqueous solution-based detection systems. In the present review, reported detection methods by using various PDA structures are summarized with updated references.