[ $^{31}P$ ] powder pattern spectra were measured to investigate the aspects of the interaction between the MLV (Multilamellar vesicle) and PMAP-23, a membrane of cathelicidin family and then CSAs(chemical shift anisotropy) were calculated to indentify the extent of perturbation of phospholipid mobility by the peptides. We found that acidic phospholipid interacts strongly with PMAP-23, and the analogues which modified to increase the amphipathic property showed that larger change of CSA. The analogue which introduced positive charge showed the same effects with amphipathic property.