To separate and purify an alkenylsalicylic acid little in coloration in a high purity and in a high yield by recrystallizing the mixture of the alkenylsalicylic acid with an alkenylresorcinol and an alkenylphenol.

This method for separating and purifying an alkenylsalicylic acid comprises dissolving the mixture of the alkenylsalicylic acid of formula I (R is a 13-17C hydrocarbon group having a double bond number of 0-3) with an alkenylresorcinol of formula II (R1 is a 13-17C hydrocarbon group having a double bond number of 0-3; R2 is H, CH3) and an alkenylphenol of formula III in a solvent, while controlling the content of water to ≤0.2 pts.wt. per 10 pts.wt. of the mixture, and subsequently cooling the solution at -45 to -180°C to deposit and separate the crystals of the alkenylsalicylic acid contained in the mixture. A solvent such as n-pentane is added in an amount of 5-2,000 pts.wt. per 10 pts.wt. of the alkenylsalicylic acid. The mixture is obtained from a plant such as Anacardium occidentale, etc.