Provide are a pattern forming method including a step (1) of forming a film using an actinic ray-sensitive or radiation-sensitive resin composition including a resin having an acid-decomposable repeating unit capable of decomposing by the action of an acid to generate an acid having a pKa of 3.0 or less, a step (2) of exposing the film using actinic rays or radiation, and a step (3) of carrying out development using a developer including an organic solvent after the exposure to form a negative tone pattern; and a method for manufacturing an electronic device, including the pattern forming method.