Blackstart following a power system blackout is a very complicated issue. Reasonable blackstart scheme plays a very important role in the fast restoration of the power system. This paper applies DEA/AHP method in which data envelopment analysis（DEA） is combined with analytic hierarchy process（AHP） to assess and sort the power system blackstart schemes. DEA/AHP possesses the advantages of both DEA and AHP， and in the meantime avoids the shortcomings of both methods， such as the subjectivity and randomness of man-made judgement matrix in AHP and the incapability of DEA to sort all the schemes at the single scale. Assessment of blackstart schemes is conducted for Tianjin power network to demonstrate the feasibility and effectiveness of DEA/AHP method that has led to an optimal scheme.