Due to the European sovereign debt crisis，as a so-called“global actor”，Britain has to adjust its defence policy with some special features. Firstly，Britain’s armed force tends to reduce its quantity，while improving its quality. Secondly，although Britain still sticks to Anglo-American Special Relationship and intergovernmentalism，it has to involve into European defence integration more deeply，especially paying more attention to implement its defence cooperation agreement with France. Thirdly，both scale and scope of Britain’s overseas military operations will shrink；therefore，Britain may incline to depend more upon joint actions with its allies.