The transport of molecules and ions through biological nanopores is governed by interaction networks among restricted ions,t ransported molecules,a nd residue moieties at pore inner walls.H owever,i dentification of such weak ion fluctuations from only few tens of ions inside nanopore is hardt oa chieve owing to electrochemical measurement limitations.H ere,w ed eveloped an advanced frequency method to achieve qualitative and spectral analysis of ion interaction networks inside an anopore.T he peak frequency f m reveals the dissociation rate between nanopore and ions;t he peak amplitude a m depicts the amount of combined ions with the nanopore after interaction equilibrium. A mathematical model for single-molecule frequency fingerprint achieved the prediction of interaction characteristics of mutant nanopores.T his single-molecule frequency fingerprint is important for classification, characterization, and prediction of synergetic interaction networks inside nanoconfinement.