Kinship network is made up of marriage and parent-child relationship. Searching a special relationship on a huge kinship network is very difficult. This paper proposed two algorithms by extending breadth-first-search method: radius-search and directional-search. The data of the kinship network was extracted from Hebei province population database, which included about 4150000 vertexes, and about 10880000 edges. The network stored bilateral relationships, which declined some unnecessary back tracking. The experimental results show that the kinship retrospect algorithm can exactly locate some specific persons by the network. At the same time the algorithms can achieve high performance and guarantee high flexibility.