This paper proposes a mathematical approach to the analysis of disassemblability of a product for generating stable robotic assembly sequences. The disassemblability of a part, which represents a cost for disassembling the part from a base assembly, is derived in terms of both separability of a part from a base assembly and motion instability of the base assembly. Then, stable robotic assembly sequences are found in the list of parts, each of which is sequentially chosen to have a locally maximum disassemblability. To show the effectiveness of the proposed method, case studies are presented for industrial products. The results are compared with those of previous researches. The comparison shows that the proposed method can effectively generate stable robotic assembly sequences and provide essential informations on fixture design.