Timely detection of trace analytes such as heavy metal ions, glucose and disease markers, which have significant negative impacts or harms to the environment and human health, is of great importance for environmental protection, disease treatment and epidemic prevention. Smart polymeric materials, which can respond to various external stimuli via changing the functional monomers, are highly potential in applications in the fields of biological and chemical detections. However, the changes in the properties of the smart polymeric materials in response to stimulus signals are usually difficult to detect trace analytes. Therefore, efficient conversion and amplification of biological and chemical signals into easily readable signals is critical for detecting trace analytes. Recently, detection technologies that can convert and amplify the trace analyte signals into simple readouts have attracted much attention. In this work, recent progress in sensitive detection technologies based on smart polymeric materials was reviewed, and detection technologies based on smart polymeric materials that converted the trace analyte signal into electrical, flow-rate-based and optical signals were highlighted. It mainly included the following contents: piezoresistive pressure sensors combined smart hydrogels converting volume change into voltage change, smart gating membranes assembled smart polymer chains or nanogels on the membrane pores converting the conformational change into trans-membrane flux change, smart microgels incorporated in microchannels converting the volume change into the flux change, smart photonic crystal hydrogels converting volume change into shift change in diffraction peaks, microcantilevers combined smart polymer chains or hydrogels converting the conformational change into the position change for laser deflection, smart hydrogel gratings converting the height and refractive index change into the change in diffraction efficiency. Finally, the perspectives and challenges of sensitive detection technologies based on smart polymeric materials were discussed. This review provided the valuable information and guidance for rational design and application of detection technologies based on smart polymeric materials.