To provide treatment information for the mastitis caused by S. uberis in Japan, we aimed to clarify AMR patterns of the isolates from bovine milk mainly in Chiba. AMR phenotyping/genotyping [blaZ–erm(A)–erm(B)–mef(A)–linB–lnuD–tet(M)–tet(O)–tet(K)–tet(L)–tet(S)] and multilocus sequence typing were performed to analyze relationships between AMR patterns and clonal complexes (CCs). Resistance to tetracycline-, macrolide-, and lincosamide-classes was mainly associated with possession of tet(O), tet(S), erm(B), linB, and lnuD genes. CC996 was significantly associated with multidrug resistance (P <0.0001). These findings will aid Chiba farm animal clinics in treating bovine mastitis.