Despite the neuropsychology literature provide reliable evidence of impaired executive functions in obsessive-compulsive disorder (OCD), it has not been determined whether these deficits are prior to onset of the disorder or they begin to appear as consequence. To investigate whether recent onset of OCD in adolescence is characterized by executive functioning difficulties in behavioral inhibition, attentional flexibility, and decision-making. Executive functions were compared in adolescents with recent (past year) appearance of OCD symptoms (n = 40) and control group (n = 40). Three computerized tests within the CANTAB battery were completed by all subjects (the Affective Go/No Go task, the Intra-Dimensional, Extra-Dimensional Set-Shifting task, and the Decision-Making task). Using one-way ANOVA showed that compared with control group, the OCD adolescents displayed a bias towards negative stimuli with less errors on sad and hopeless words on the Affective Go/No Go task. They also made faster decisions while they bet more of their available points compared to controls, in the Decision-Making task. Adolescents with recent OCD diagnosis (less than one year) showed greater attention towards sad and hopeless stimuli and more impulsive behavior when making decisions. However, they were able to switch attentional set to neutral stimuli. These findings suggest that executive functioning impairments can characterize adolescence OCD from early beginning of the disorder.