Zeolite is aluminosilicate containing pores and cavities that are usually used as absorbent materials. Nano zeolite - molybdate was used as a ripeness indicator of avocado. The ripeness indicator was made by dissolving molybdate in hydrogen peroxide (H2O2) and mixed with nano zeolite. This study was aimed to determine the colour change of indicator, and the relationship between the changing colour of indicator and the ripening of avocado. The ripeness indicator was prepared used activated nano zeolite with HCl 1 N for 24 h, then mixed with 4 mL peroxomolybdate. Nano zeolite-molybdate tablets was packed using 0,04 mm thick of LDPE plastic, and it was inserted inside avocado packaging. The ripeness indicator would identified by the ethylene production of avocados, and resulted changing the indicator colour from yellow to blue. The yellow colour would represent unripe avocado, but the blue colour would represent ripe avocados. The colour changing was related with the decrease of avocado quality during 10 days storage with the rate of weight loss 0.0113%, the rate of sugar level 0.7182% and the rate of avocado hardness 2.1132% by day.