Synchronous behavior of neural populations has been related to cognitive processes as attention, learning and has been considered as hallmarks of neurological disorders. The computational models of neural structures, even the simple ones, could give informative results which can improve our understanding of cognitive processes, arising due to collective activity of neurons. Here, a neurocomputational model for investigating the role of dopamine level on the synchronized behavior of medium spiny neurons in striatum is given. The model is composed of point neurons and dynamic synaptic connections and the excitatory connections of medium spiny neurons are modulated according to spike time dependent plasticity rule. The results convey that dopamine level has opposite effect on the synchronization of D1 and D2 type medium spiny neuron populations. Also, it is shown that spike timing dependent plasticity enhances the synchronized behavior.