Solid-state nanopores have previously been applied to the recognition and detection of DNA and proteins as a powerful tool for single-molecule detection. Here, we use silicon nitride nanopores to identify short peptides of six amino acids in length and their dimers. The experimental results show that the blocking current of the dimer is close to twice as large as that of the monomer. Due to the lower charge, the probability of the dimer passing through the pore at voltages below 100mV is low. In addition, the results of the mass spectrometry assay provide evidence for a translocation event of the short peptides and their dimers.