Chlormequat (cycocel or CCC), the plant growth retardant, was evaluated for its ability to control plant height in Brassica oleracea cultivar ‘Kamome White’ and ‘Nagoya Red’. Different concentrations of CCC (0, 500, 1000 and 1500 mg/L) were sprayed and drenched on plants 40 days after transplanting. Data were recorded the 60 and 90 days after transplanting. The 1500 mg/L of CCC resulted in about 50 and 20% shorter plants than the control plants, 60 and 90 days after transplant, respectively. The growth of Brassica oleracea cultivar ‘Kamome White’ and ‘Nagoya Red’ decreased with increasing the concentration of CCC. Foliar sprays of CCC controlled plant height of both cultivars. The least record of plant height was obtained by application of 1500 mg/L CCC via spraying method in cultivar ‘Kamome White’ after 60 and 90 days (9.94 and 11.59 cm, respectively). The effect of cultivar type has been significant at p£0.01 level on all measured traits.