This paper was to analyze the fusion between the organic and inorganic characteristics performed in architecture and urbanism, especially on the characteristics found in the works of Archigram group who was very active during 1960s and 70s. Generally, it was thought that Archigram drew its ideas mainly from a mechanist metaphor and that the diagrams of its members were based on the notion of the material obsolescence, which could be placed in a British tectonic tradition. But, Archigram’s works has been continually influenced by the biological-organic analogy from the birth of the group to its dissolution. Simply, the importance that the biological-organic analogy takes in the works of Archigram has changed periodically according to the change of its members. We can divide generally Archigram group in two parts : on one hand, nascent members such as Peter Cook, Dennis Greene, Michael Webb ; on the another hand, three members who participated from LCC such as Warren Chalk, Ron Herron, Dennis Crompton. As the new three LCC members participated, Archigram Group focalized on the technological part more than ever. But, when its members dispersed geographically and professionally, its biological-organic analogy came out again at the surface of their works. However, Archigram's organic and inorganic characteristics did not always adhere in opposing position with each other and took the form of coexistence in harmony at the same period. That is, the works of Archigram were persuing the creation of community that nature, technology and architecture could communicate and harmonize with each other through the intergration between organic and inorganic characteristics. The reason why Archigram became the one of the most excellent architectural avant-garde group in the 60s was mainly to receive asssitance with the fact that two small groups having contradictory tendencies got together and formed the Archigram group.