Two　cupric　complexes　containing　methylbenzoic　acid　have　been　prepared　and　crystallized　by　solvent　evaporation　method　in　DMF.　The　single-crystal　X-ray　crystallographic　analysis　reveals　that　they　are　dicaryon　complexes.　Complex　1　with　formula　of　[Cu-2(m-MBA)(4)DMF2]　crystallizes　in　monoclinic　with　space　group　of　P2(1)/c　and　complex　2　with　formula　of　[Cu-2(o-MBA)(3)(o-phen)2]center　dot　NO3　center　dot　H2O　crystallizes　in　triclinic　with　space　group　of　P　(1)　over　bar.　The　weak　interactions　including　C-H　center　dot　center　dot　center　dot　O　hydrogen　bonds,　C-H　center　dot　center　dot　center　dot　pi　interactions　and　pi-pi　stacking　in　the　structures　of　two　complexes　are　observed　from　the　X-ray　crystallographic　data.　In　addition,　there　are　still　classical　hydrogen　bonds　in　2.　The　different　strength　of　intermolecular　interaction　in　the　structure　is　reflected　on　their　different　thermal　stability　measured　by　thermal　gravimetric　analysis　and　2D-IR　correlation　spectroscopy　of　two　complexes.　The　study　of　weak　interactions　is　meaningful　to　provide　supporting　data　for　supramolecular　chemistry　theory　and　potential　applications　in　molecular　biology.