To provide a resin in which whose directional property, anisotropy, or the like to its optical transparency or photopermeability are given, a photosensitive resin composition using the resin, and a pattern formation method using the composition.

The resin is constituted of a unit-M described by formula (1): -[R3-(Y)p]n-R4, wherein Y is a group having an unsaturated bond; R3 and R4 are each an aromatic or non-aromatic ring group which may have a substitutional group, and n and p are 0 or 1. The resin may be a homopolymer or copolymer of a polymerizable compound described by formula (2), wherein A and B are each a bonding group; X is a spacer; R1 is a hydrogen atom or a methyl group; R2 is an alkylene group or an arylene group; a, b and m are each 0 or 1; -M group is the same as described by formula 1, but it does not occur that a and b are 0 simultaneously.