AdenseseismicnetworkwasinstalledinthecapitalregionofChinainrecentyears,whichmakesitpossibletoresolvethefocalmechanismsofsmallearthquakes.Wegatheredlargeearthquakefocalmechanismsfromthelastfiftyyearsandmoderateorsmallearthquakefocalmechanismsfrombetween2002and2004,andcalculatedthepresenttectonicstressfieldofthecapitalregionbythegridsearchmethod,whichweighsdifferentsizedearthquakesandcanimprovetheaccuracyofthestressfieldinversion.Theanalysisofinversionresultsofdifferentsub-regionsshowsthattheazinuthofthemaximumprincipalcompressivestressaxisisNE43°-86°intheBeijing-Zhangjiakou-Datongarea,NE38°-86°intheTangshanarea,andNE79°-81°intheXingtaiarea.Inversionresultsofthispaperaresimilartopreviousresults,whichprovesthecorrectnessoftheapproach.Asrevealedbytheresults,thestressfieldofthecapitalregionischaracterizedbyoverallconsistencyandsub-regionaldifferences.Thisstudyprovidesreferenceforearthquakemechanismexplanationandgeodynamicsresearch.
