Interference control and time perception are mediated by common neural networks, including the frontal and parietal lobes, the cerebellum and the basal ganglia. Previous studies have shown that while time perception develops early in life, interference control seems to follow a protracted course of maturation into late adolescence. Thus, the current study examined developmental changes in neural activation and functional interaction between brain regions during a combined time discrimination and interference control task using fMRI. Thirty-four participants, aged 8-15 years, were scanned while performing a spatial stimulus response compatibility (SRC) task and a time discrimination (TD) task using identical stimuli. We found shared neural activation in a fronto-parieto-cerebellar network as well as task-specific patterns of psychophysiological interaction with positive coupling between the right inferior frontal gyrus (IFG), the superior parietal lobes bilaterally, the contralateral IFG and the thalamus during interference control and positive interactions between the right IFG and bilateral cerebellar activity and the thalamus during time discrimination. Developmental changes in task performance and brain activation patterns were only observed during the SRC task, with increased neural activity in the left inferior parietal gyrus and positive coupling between fronto-parietal brain regions that was only observed in the adolescents group. These results suggest that although both cognitive tasks rely on a shared neural network, distinct developmental curves of brain activation and connectivity could be observed associated with differential maturation patterns underlying cognitive development.