A research has been done to obtain hydrophobic layer on 1XXX allumunium alloy which made by one step anodizing to cover the surface of the metal with the protective oxide layer and chemically modified by using stearate acid with the variation of time immersion for 5, 10, 15 and 20 hours. The making process of hydrophobic layer uses an easy and eco friendly method. First, polishes the allumunium using the abrasive paper and deionized water using ultrasonic cleaner. Then the allumunium is treated with a chemical solution which contains stearate acid (2,6%), alcohol, and deionized water (1:1) and heated to 60⁰C. The results of the immersion cleanse by alcohol and deioniation so it is pollutant free, and then the wettability test done with water and straw. The results of the test shows that the allumunium anodizing hydrophobic, which the contact angle test marked by 133⁰ with the immersion time for 20 hours, then the morphology of the surface observed using SEM SU-350 showed a fiber like structure and tied to each other, meanwhile the surface of anodizing allumunium without modification of stearate acid has porous and hollow structures.