Disclosed is a novel vector for plant transformation. The vector is a cosmid vector having the entire length of 15 kb or shorter and also having the following properties: 1) the vector contains a replication initiation point for IncP plasmid but does not contain a replication initiation point for other plasmid； 2) the vector contains trfA1 gene for IncP plasmid； 3) the vector contains oriT for IncP plasmid； 4) the vector contains incC1 gene for IncP plasmid； 5) the vector contains a cos site for a lambda phage and the cos site is located outside of T-DNA； 6) the vector contains a drug-resistant gene which can be expressed in Escherichia coli and a bacterium belonging to the genus
