Abstract: A practical mission reliability index allocation approach is p roposed. The essence of m ission reliability index allocation is analyzed, and the rinciples of the ratio - composed methodand expert rating allocationmethod which are applicable to basic reliability index allocation are put for ward to mission reliability index allocation. An engineering m ission veliability index allocationmethod is given with the tabulated, no rmalized working procedure. Finally, the accuracy and cenvergence of this practical approach are discussed.

Key words: missions, reliability, index, allocation