In this paper, we have reported the calculated results of anisotropy parameter (Pl) and angular momentum transfer parameter (L) for positron (electron) scattering by Calcium (Ca) atom using close coupling approximation method in the framework of R-matrix theory at 20eV. Since this theory has deep root in nuclear physics, it also provides better results in atomic and molecular physics. The authors have compared the reviewed results with available theoretical results. A good agreement between these results shows that the present method gives better understanding for the positron (electron)-atom scattering.