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Autochthonous single (Ent+) or multiple (m-Ent+) enterocin-producing strains of dairy enterococci show promise for use as bioprotective adjunct cultures in traditional cheese technologies, provided they possess no pathogenic traits. This study evaluated safety, decarboxylase activity, and enzymatic (API ZYM) activity profiles of nine Ent+ or m-Ent+ Greek cheese isolates previously assigned to four distinct <i>E. faecium (</i>represented by the isolates KE64 <i>(entA),</i> GL31 <i>(entA)</i>, KE82 <i>(ent</i>A<i>-ent</i>B<i>-ent</i>P) and KE77 <i>(ent</i>A<i>-ent</i>B<i>-ent</i>P<i>-bac31)</i>) and two <i>E. durans</i> (represented by the isolates KE100 <i>(ent</i>P<i>)</i> and KE108 <i>(ent</i>P<i>-bac31-cyl</i>)) strain genotypes. No strain was <i>β</i>-hemolytic or harbored <i>van</i>A and <i>van</i>B or the virulence genes <i>agg, ace, espA, IS16, hyl</i>, or <i>gel</i>E. All strains were of moderate to high sensitivity to ampicillin, ciprofloxacin, chloramphenicol, erythromycin, gentamicin, penicillin, tetracycline, and vancomycin, except for the <i>E. faecium</i> KE64 and KE82 strains, which were resistant to erythromycin and penicillin. All cheese strains showed moderate to strong esterase-lipase and aminopeptidase activities and formed tyramine, but none formed histamine in vitro. In conclusion, all Ent+ or m-Ent+ strain genotypes of the <i>E. faecium/durans</i> group, except for the <i>cyl</i>-positive <i>E. durans</i> KE108, were safe for use as adjunct cultures in traditional Greek cheeses. Further in situ biotechnological evaluations of the strains in real cheese-making trials are required.