Synthetically produced miRNA molecules plays an important role as biomarker to examine and investigate the diagnosis of some diseases including cancer. In order to develop a sensitive electrochemical biosensor system for the detection of miRNA molecules, the anti-miRNA molecules are synthesized and immobilized on the biosensor surfaces and observe the signal changes via a proper measurement. Immobilization time and temperature along with the anti-miRNA concentration are critically important for an appropriate observation of the miRNA detection sensitivity of the prepared biosensor system. In this regard, synthetically produced anti-miRNA (anti-miR451(G)) was purchased and diluted into different concentration by using phosphate buffer solution. Then, the solutions were immobilized on the screen printed electrodes (SPEs) and the guanine oxidation signal of the anti-miRNA molecules were observed via differential pulse voltammetry method (DPV). An appropriate concentration of the solution was selected and dropped on the SPEs and held on at different temperatures (-18, +5 and +25 oC) for 1, 3, 14 and 21 days and DPV measurements were conducted to investigate the optimum immobilization time and temperature. The result shown that guanine oxidation signal was increased by increasing the concentration of the genetic molecules in the immobilization solution and increased less after that point when the concentration increased more because the surface reached to a certain saturation value . The guanine oxidation signal revealed that the best suitable storing temperature after the immobilization was +5 oC determined.