Protein phosphorylation plays a critical role in the regulation of many cellular functions. Phosphoproteomic analyses facilitate an in-depth understanding of such phosphorylation-dependent signaling networks. The use of mass spectrometry in phosphoproteomics has been especially successful, but the approach largely depends on an efficient method to enrich phosphopeptides from complex mixtures. We have developed a novel, effective soluble nanopolymer-based phosphopeptide enrichment technique, termed PolyMAC (polymer-based metal ion affinity capture). The homogenous, hyperfunctional nature of PolyMAC reagent makes it a more competent choice for highly efficient phosphopeptide binding and isolation, which was demonstrated through several applications with simple protein mixture and complex cell extract.