During　the　outbreak　of　the　COVID-19,　China　implemented　an　urban　lockdown　in　the　first　period.　These　measures　not　only　effectively　curbed　the　spread　of　the　virus　but　also　brought　a　positive　impact　on　the　ecological　environment.　The　water　quality　of　urban　inland　river　has　a　significant　impact　on　urban　ecology　and　public　health.　This　study　uses　Sentinel-2　visible　and　near-infrared　band　reflectance　and　the　Normalized　Difference　Turbidity　Index　(NDTI)　to　analyze　the　water　quality　of　the　Haihe　River　Basin　during　the　control　period　of　COVID-19.　It　is　found　that　during　the　lockdown　period,　the　river　water　quality　was　significantly　improved　compared　to　the　same　period　in　2019.　The　average　NDTI　of　the　Haihe　River　Basin　in　March　decreased　by　0.27,　a　decrease　of　219.06%;　in　April,　it　increased　by　0.07,　that　is　38.38%.　Further　exploration　using　VIIRS　lights　found　that　the　brightness　of　the　lights　in　the　main　urban　area　was　significantly　lower　in　February,　the　beginning　of　the　lockdown.　However,　as　the　city　was　unblocked,　the　lights　rose　sharply　in　March　and　then　recovered　to　normal.　There　is　obvious　asynchrony　in　changes　between　river　turbidity　and　light.　The　results　can　help　understand　the　impact　of　human　activities　on　the　natural　environment.