In this research pix effect as plant growth regulators on growth parameters of cotton plant were evaluated. Cotton seeds (Gossypium hirsutum L. cv Ci-Ocra) were planted under pots condition in photoperiods 20 ± 2 ºC and 14– h light /10 –h dark. After 80 days, pix was sprayed in different concentrations include 0 (control), 0.5,1, 1.5, 2 L.ha-1 twice within ten days on shoot of cotton plants. Three weeks after spraying were separated root from shoot and growth parameters were determined. The results showed that pix different treatments decreased stem length, leaf number and leaf area in comparison with control .Also pix in higher concentration reduced shoot to root rate, nodes number. Our data showed pix application in concentration 2 L.ha-1 increased fresh and dry weight in leaf cotton. Parameters as root length, fresh and dry weight of stem and root did not change significantly at different concentrations of pix.