The device fabricated in this study was an internal ion-gated organic electrochemical transistors (IGTs) using screen printing technology on a flexible polyimide (PI) film substrate. This fabrication method is a cost-effective and simple method without existing deposition techniques or complicated processes. The conductive polymer, poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS), commonly used as a channel material in organic electrochemical transistors (OECTs), was blended with D-sorbitol to enable a self-ion (de)doping mechanism within the channel, eliminating the requirement for an external electrolyte. The screen-printed IGT exhibited enhanced conductivity and performance compared to conventional OECTs. Analysis of the physical and chemical properties of PEDOT:PSS with D-sorbitol revealed a significant reduction in sheet resistance. The surface analysis further confirmed an enhancement in crystallinity. Electrical performance evaluation involved a comparative study with conventional OECTs. The IGT device demonstrated a 4 times increase in output curve characteristics at VGS = 1.6 V compared to OECTs. Additionally, the ION/IOFF ratio was 4.3 times higher for the IGT. Calculations of μC* to assess device mobility indicated a notable improvement, with values of 0.9578 F V-1 s-1 cm-1 for IGT compared to 0.6987 F V-1 s-1 cm-1 for OECTs. In time constant analysis, τOECT = 0.50 s and τIGT = 0.34 s indicate that IGTs have a faster response time.