• Myrtle plant parts presented unique fingerprinting by HPTLC. • The highest quercitrin content was found in the myrtle floral buds by HPLC method. • Myrtle floral buds showed the highest antioxidant activity. • The highest myricitrin amount was calculated in myrtle leaves by HPLC. • Myrtle leaves exhibited the highest anticancer activity on the HT-29 cell line. • Myrtle parts showed strong antimutagenic activity with/-out metabolic activation. Myrtus communis L. (Myrtle) plant parts have been traditionally used to treat various disorders. Herein, we aimed to compare the chemical compositions, antioxidant, anticancer, and anti/-mutagenic activities of the hydroalcoholic extracts prepared from floral buds, flowers, leaves, and fruits of Myrtle. Quercitrin, myricitrin, and myricetin 3- O -β-galactopyranoside were identified in all plant parts analysed by HPTLC, MS, and NMR spectroscopy. A newly developed and validated HPLC method carried out the quantification of quercitrin and myricitrin in the extracts. The highest quercitrin content was found in floral buds as 18.5 ± 0.1 mg/g, whereas the highest myricitrin content was calculated in leaves as 25.0 ± 0.4 mg/g. The highest antioxidant activity was determined in floral buds by DPPH, ABTS, and FRAP tests and the assay of superoxide anion generated by xanthine oxidase. Additionally, HPTLC-DPPH revealed that luteolin, gallic acid, quercitrin, myricitrin, and myricetin 3- O -β-galactopyranoside contributed to the antioxidant activity of the extracts. The hydroalcoholic extract prepared from the leaves exhibited the highest anticancer activity against human colorectal cancer cell line, HT-29 with IC 50 value of 8.2 µg/mL in WST-1 assay. None of the samples in the Ames test were found to be mutagenic at all tested concentrations. In fact, results of the antimutagenicity assay revealed that leaves exerted the strongest activity against the tested strains. The results indicated the potential of Myrtle plant parts to develop herbal medicinal products or use as a food additive.