This　study　sought　to　understand　how　the　features　of　proteins　impact　the　properties　of　nanoparticles　assembled　using　the　pH-shifting　approach　and　the　mechanism　behind.　Four　legume　protein　isolates　from　faba　bean,　mung　bean,　soy,　and　pea　were　fractionated　into　natural　aqueous-soluble　(Sup)　and　aqueous-insoluble　(Sed)　fractions,　which　were　proved　to　serve　as　shell　and　core,　respectively,　for　the　pH-driven-assembled　nanoparticles.　Using　zein　instead　of　Sed　fractions　as　the　core　improved　size　uniformity,　and　particle　size　can　be　precisely　controlled　by　adjusting　core/shell　ratios.　Using　the　proteomic　technique　and　silico　characterization,　the　features　of　identified　proteins　indicated　that　hydrophobicity　rather　than　molecular　weight,　surface　charge,　etc.,　mainly　determined　particle　size.　With　molecular　docking,　structural　analysis,　and　dissociation　tests,　the　assembly　of　zein/Sup-based　nanoparticles　was　dominantly　driven　by　hydrophobic　interactions.　This　study　provides　constructive　information　on　the　correlation　between　protein　features　and　the　properties　of　pH-driven-assembled　nanoparticles,　achieving　a　precise　control　of　particle　size.