The Aim of the present study was to evaluate the suitability of Nitanium Connecticut intrusion arch in leveling deep curve of Spee. The sample of this study consisted of 10 Class II division 1 growing female patients with a mean age of 13.28 (± 1.43). Lower short 0.017 x 0.025 inch nitanium Connecticut intrusion arches were used for all patients after the teeth had been initially aligned. Superimposition of lateral cephalograms taken before and after leveling for each patient was made to determine the anteroposterior and vertical displacement of the lower incisors as well as the vertical position displacement of lower first molar. Statistical paired t- test was done to determine significant difference between the pre-leveling and post-leveling measurements. In the present study the lower incisors were significantly intruded by 2.63 mm in 5.2 months (P < 0.001). Significant lower incisors proclination as indicated by the increase in the angle of the axis of the most protruded lower incisor to the Mandibular plane (MP), Frankfort horizontal plane (FH) and NB Plane by 3.5°, 4.125°, 2.625° respectively (P < 0.001) as well as the increase in the distance from Ii to NB line by 1.688 mm. There was also a significant decrease in the amount of overbite by 2.813 mm (P < 0.001). Mandibular lower first molars vertical position was not significantly changed(0.625mm P > 0.05). As well as no significant change in the following measurements; lower facial height (0.5mm P > 0.05), posterior facial height (0.365mm P > 0.05) and the FMA angle (0.375mm P > 0.05). It was determined that the Connecticut intrusion arch was effective in intrusion of lower incisors.