In recent decades a group of enzymes produced by bacteria called β-lactamase has been in constant study due to its ability to provide bacteria with multi-resistance to β-lactam antibiotics such as carbapenems, cephalosporins, monobactams, and penicillins. This work presents a metric that identifies characteristic features of this important group of enzymes based on the protein polar profile. To this end, we utilized a computational mathematical method called polarity index method (PIM), which was already used by this team in the study of several peptides and protein groups, to obtain a “fingerprint” of β-lactamase proteins. The verification of this method aimed at the identification of β-lactamases (divided in four subgroups) was carried out using all antimicrobial proteins from the UNIPROT database (September 10, 2017) and the APD3 Database (September, 10, 2017). The test plan considered the totality of reviewed proteins in both databases, and the verification of their measurement of the disorder level. The efficiency of the polarity profile method exceeds 80% taking into account the false positive and false negative protein groups. According to these results, the polarity index method identifies each of these four β-lactamases group with a high level of efficiency.