In the article, a very low loss terahertz (THz) photonic crystal fiber (PCF) has been proposed and investigated precisely. The investigation results have proved that the designed PCF shows very low effective material loss (EML) of 0.03 cm⁻¹ at 1.0 THz that simultaneously indicates about 85% reduction of bulk absorption loss of the hosting material. Moreover, other optical parameters of the PCF such as effective mode area (EMA), confinement loss (CL), dispersion, V-parameter and figure of merit (FOM) have been investigated also. The proposed PCF testifies a flatted dispersion developed from 0.96 THz to 1.10 THz. The investigated outcomes indicate that the proposed PCF will be a good candidate for THz or T-ray transmission as well as in the area of photonics devices also.