Abstract: Provided is a method using micro/nano bubbles for enhanced in situ remediation of polluted groundwater, comprising: arranging a water injection pipe (7) at an upstream location of an area where groundwater is polluted; introducing thereto a micro/nano bubbles-containing water having nutrient salt(s) therein; transferring the micro/nano bubbles-containing water having nutrient salt(s) with the movement of groundwater to the polluted area, decomposing organic pollutants or continuously replenishing electron acceptor(s)/donor(s) for microorganisms to facilitate the degradation and removal of the organic pollutants; meanwhile, arranging a water extraction pipe (17) at the downstream of the polluted area to extract water and form a groundwater flow-field; setting up a monitoring well for real-time monitoring and analyzing of parameters during the removal process of the organic pollutants and adjusting the occurrence time and the amount of aeration of the micro/nano bubbles.