The main purpose ofthis paper is to validate the efficiency and accuracyof the Half-Sweep Arithmetic Mean (HSAM) method using the fourth orderfinite difference approximation equation to solve one-dimensionalPoisson's equation. In this paper, we formulate the Full-Sweep andHalf-Sweep Arithmetic Mean methods, namely FSAM and HSAMrespectively. Finally some computational experiments were conductedto prove that the fourth-order solver using the HSAM methods issuperior to the FSAM method.