In this research, for the first time a novel technique was presented for early detection of diabetes based on an electrochemical sensor fabricated by modifying a screen printed carbon electrode with graphene oxide, gold nanourchin, and thiol-probes (hematoxylin) for target molecules. During the fabrication of this nanosensor, parameters such as graphene oxide concentration, gold nanourchin concentration, stabilization method, probe concentration, probe fixation time at the electrode surface, hematoxylin concentration, hematoxylin accumulation time and hybridization process were studied and optimized. The specific function of the designed biosensor versus the target miRNA was explored. The performance of the proposed sensor was evaluated in miRNA detection, so that the designed sensor was capable of detecting target miRNA in the linear range of 0.2-800 pM and with a detection limit of 0.05 pM. Also, the suggested biosensor has a very high specificity in detecting miRNA target (miR-200b) in presence of complementary miRNAs, as well as miRNAs with a different base from the target molecule and also from the miR-29a-3b as non-complementary miRNA.