Avocado seeds could be extracted into natural dyes because they contained of tannin. Tannin as a dyes substances would cause brown or brownish color. The weakness of natural dyes in the textile dyeing process that has a low fade resistance. Therefore, the dyeing process of textile materials with natural dyes were needed fixation process in order that color had a well fade resistance. The natural dyes from avocado seeds had been applicated on cotton textile. The fade resistance of natural dyes had been tested by varying the mass of Al2(SO4)3as a fixation to the value of light intensity difference on the residue water of the cotton textile washing. The treatment used the mass variation of 10g to 60g Al2(SO4)3by dyeing for 10 minutes. The study design consisted of avocado seeds extraction as a source of natural dyes, mordanting of cotton textile, dyeing of cotton textile in a dye solution, fixation of cotton textile and test the fade resistance of natural dyes on cotton textile using a luxmeter after washing by water and detergent solution. The results showed that the sample used a mass of 60g Al2(SO4)3produced the smallest color fade degree with the value of light intensity difference on the residue water was 9.58lux of washing by water and 3.11lux of washing by detergent solution. The higher mass of Al2(SO4)3was used as fixation on cotton textile, the natural dyes of avocado seeds had a better fade resistance. The using of 60g Al2(SO4)3sample as a fixation material was effective for kept the fade resistance of natural dyes from avocado seeds on cotton textile.