To provide a method for efficiently and stably producing an aliphatic dicarboxylic acid crystal having a large surface area and high acicularity making the composition to slurry easily.

This method for producing the acicular aliphatic dicarboxylic acid crystal in which the average value in the ratio of the largest crystal length to its width (aspect ratio) is 2-20, comprises crystallization-recovering a crystal of aliphatic dicarboxylic acid from an aqueous solution containing at least one selected from aliphatic dicarboxylic acids and salts thereof derived from biomass resources.