This paper presents an overview on the recent advance in the determination of environmental pollutants by immunosensors, which are classified as mass-based, optical and electrochemical sensors according to the signal transduction mechanism. New immunosensors based on total internal reflection fluorescence (TIRF), optical waveguide lightmode spectroscopy (OWLS) and surface plasma resonance (SPR), are described in detail. Advances in signal amplification, multiple-analyte determination, sensor regeneration, automation and miniaturization are discussed, followed by a perspective at the end of the paper.