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We report a multi-wavelength study of two evolved planetary nebulae(PNs)M 2-55 and Abell 2.Deep optical narrow-band images([O Ⅲ],Hα,and[NⅡ])of M 2-55 reveal two pairs of bipolar lobes and a new faint arc-like structure.This arc-shaped filament around M 2-55 appears as a well-defined boundary from southwest to southeast,strongly suggesting that this nebula is in interaction with its surrounding interstellar medium.From the imaging data of Wide-field Infrared Survey Explorer(WISE)all-sky survey,we discovered extensive mid-infrared halos around these PNs,which are approximately twice the size of their main nebulae seen in the visible.We also present a mid-resolution optical spectrum of M 2-55,which shows that it is a high-excitation evolved PN with a low electron density of 250 cm-3.Furthermore,we investigate the properties of these nebulae from their spectral energy distributions(SEDs)by means of archival data.