A polyimide resin represented by the following general formula (I): wherein, R1 represents a divalent organic group having an aromatic ring or an aliphatic ring; R2 represents a divalent organic group having a weight average molecular weight of 100 to 10,000; R3 represents a divalent organic group having an aromatic ring, an aliphatic ring or an aliphatic chain; R4 represents a tetravalent organic group having 4 or more carbon atoms; n represents an integer of 1 to 100; m represents an integer of 2 to 100; and x represents an integer of 1 to 50. The polyimide resin has excellent pliability and flexibility while retaining strength and thermal resistance.