Concrete　structures　in　normal　service　are　often　subject　to　complex　stresses　and　are　inevitably　subject　to　the　sporadic　dynamic　loads.　The　failure　criterion　is　the　foundation　for　the　study　of　mechanical　properties　of　concrete　under　complex　loads.　Limited　by　the　test　equipment　and　other　conditions,　the　existing　dynamic　biaxial　tension-compression　strength　failure　criterion　has　a　complex　form,　lacks　of　higher　strain　rate　and　lateral　stress　ratio　range　and　has　not　yet　considered　the　coupling　effect　of　strain　rate　and　lateral　stress　ratio　comprehensively.　In　order　to　further　propose　a　more　applicable　and　accurate　failure　criterion　of　concrete　dynamic　biaxial　tension-compression　strength,　a　3D　random　numerical　model　of　cubic　concrete　is　established　on　a　mesoscale　in　this　study.　The　dynamic　tension-compression　failure　behavior　of　concrete　materials　under　different　strain　rates　and　lateral　stress　ratios　are　simulated.　The　influence　of　strain　rate　and　lateral　stress　ratio　on　the　failure　modes　and　dynamic　biaxial　strengths　of　concrete　are　discussed　respectively.　The　failure　criterion　of　dynamic　biaxial　tension-compression　strength　of　concrete　is　put　forward.　The　simulation　results　indicated　that　with　the　increase　of　strain　rate　and　lateral　stress　ratio,　the　internal　damage　of　concrete　specimen　increases　and　the　number　of　cracks　increase.　Under　dynamic　biaxial　tension-compression　loads,　with　the　increasing　strain　rate,　the　dynamic　spindle　compressive　strength　and　dynamic　lateral　tensile　strength　of　concrete　increase　gradually.　With　the　increasing　lateral　stress　ratio,　the　dynamic　spindle　compressive　strength　decreases　while　the　dynamic　lateral　tensile　strength　increases.　The　dynamic　biaxial　Tension-Compression　failure　criterion　of　concrete　proposed　in　this　paper　has　the　advantages　of　wide　range　of　applicable　strain　rate　and　lateral　stress　ratio,　concise　form,　no　longer　restricted　by　physical　test　conditions　and　considering　the　coupling　effect　of　strain　rate　and　lateral　stress　ratio,　etc.　The　established　failure　criterion　of　concrete　has　been　verified　from　different　angles.　Copyright　©　2022　Chinese　Journal　of　Theoretical　and　Applied　Mechanics.　All　rights　reserved.