Concrete　is　typical　porous　medium　permeated　by　an　interconnected　network　of　pores　and　micro-cracks.　In　the　micro　level,　concrete　is　considered　as　a　three-phase　composite　with　aggregates,　pores　and　mortar　matrix.　In　the　paper,　the　random　multi-scale　mechanical　analysis　model　is　adopted　to　study　the　macro-mechanical　properties　of　concrete　with　pores.　The　results　indicate　that　the　existence　of　pores　and　micro　cracks　has　great　influence　on　macro　elastic　modulus,　effective　strength,　residual　strength　and　other　mechanical　properties　of　concrete,　which　should　not　be　neglected　when　investigating　the　mechanical　properties　and　damage　fracture　of　concrete.