Plastic pollution has been a legacy environ-ment problems and more recently,the plastic particles,especially those ultrafine or small plastics particles,are widely recognized with increasing environmental and ecological impacts.Among small plastics,microplastics are intensively studied,whereas the physicochemical properties,environmental abundance,chemical states,bioavailability and toxicity toward organisms ofnanoplas-tics are inadequately investigated.There are substantial difficulties in separation,visualization and chemical identification of nanoplastics due to their small sizes,relatively low concentrations and interferences fiom co-existing substances (e.g.,dyes or natural organic matters).Moreover,detection of polymers at nanoscale is largely hampered by the detection limit or sensitivity for existing spectral techniques such as Transformed Infrared Spectro-scopy (FTIR) or Raman Spectroscopy.This article critically examined the current state of art techniques that are exclusively reported for nanoplastic characterization in environmental samples.Based on their operation princi-ples,potential applications and limitations of these analytical techniques are carefully analyzed.