The present invention provides a diphenyl amine derivative having the excellent solubility to a solvent and compatibility to a binding resin, an efficient production method therefor, and an electrophotographic photoconductor having the excellent sensitivity, capable of effectively preventing generation of the black dots. A diphenyl amine derivative represented by the following general formula (1) is used: (In the general formula (1), R1 to R12 each are a hydrogen atom, an alkyl group which may have a substituent, or the like, Z is a ring structure linked with a benzene ring, which is a 4 to 8-membered ring including a hydrogen atom, a nitrogen atom, an oxygen atom, a carbon atom or a sulfur atom, m1, m2, n1, n2 each are 0 or 1, m1+n1 is 1 or 2, and m2+n2 is 1 or 2.)