<jats:p>The chemical composition of the essential oils and hydrosol extract from aerial parts of <jats:italic>Calendula arvensis</jats:italic> L. was investigated using <jats:styled-content style="fixed-case">GC</jats:styled-content>‐<jats:styled-content style="fixed-case">FID</jats:styled-content> and <jats:styled-content style="fixed-case">GC</jats:styled-content>/<jats:styled-content style="fixed-case">MS</jats:styled-content>. Intra‐species variations of the chemical compositions of essential oils from 18 Algerian sample locations were investigated using statistical analysis. Chemical analysis allowed the identification of 53 compounds amounting to 92.3 – 98.5% with yields varied of 0.09 – 0.36% and the main compounds were zingiberenol 1 (8.7 – 29.8%), eremoligenol (4.2 – 12.5%), <jats:italic>β</jats:italic>‐curcumene (2.1 – 12.5%), zingiberenol 2 (4.6 – 19.8%) and (<jats:italic>E</jats:italic>,<jats:italic>Z</jats:italic>)‐farnesol (3.5 – 23.4%). The study of the chemical variability of essential oils allowed the discrimination of two main clusters confirming that there is a relation between the essential oil compositions and the harvest locations. Different concentrations of essential oil and hydrosol extract were prepared and their antioxidant activity were assessed using three methods (2,2‐diphenyl‐1‐picrylhydrazyl, Ferric‐Reducing Antioxidant Power Assay and <jats:italic>β</jats:italic>‐carotene). The results showed that hydrosol extract presented an interesting antioxidant activity. The <jats:italic>in vitro</jats:italic> antifungal activity of hydrosol extract produced the best antifungal inhibition against <jats:italic>Penicillium expansum</jats:italic> and <jats:italic>Aspergillus niger</jats:italic>, while, essential oil was inhibitory at relatively higher concentrations. Results showed that the treatments of pear fruits with essential oil and hydrosol extract presented a very interesting protective activity on disease severity of pears caused by <jats:italic>P</jats:italic>. <jats:italic>expansum</jats:italic>.