Background: The plant Dryopteris filix-mas has been used traditionally for its uterine-stimulant effects.Aim: The current study is therefore aimed at investigating and determining the effect of the leaves of D. filix-mas on uterine contractility in vitro.Setting: Fresh leaves of D. filix-mas were collected from a river bank in the south-western part of Nigeria.Methods: The leaves of D. filix-mas were cleaned, dried and extracted in methanol. The extract (0.07 µg/mL–21.0 µg/mL) was tested on the isolated mouse uteri in order to determine activity on spontaneous-induced uterine contractions. Subsequently the extract (0.005 mg/mL and 0.05 mg/mL) was tested on oxytocin-induced contraction (0.00017 ng/mL–4.98 ng/mL) in calcium-containing media, submaximal oxytocin-induced contraction (0.116 ng/mL) in calcium-free media and in the presence of high KCl-induced uterine contractions (80 mM). The extract was also subjected to mass spectrometric determination of secondary metabolites.Results: The plant extract inhibited spontaneous-induced contractions with IC50 amplitude = 658.41 ng/mL ± 0.11 ng/mL and IC50 frequency = 175.32 ng/mL ± 0.53 ng/mL. The plant extract inhibited oxytocin-induced and high KCl-induced uterine contractions (p < 0.01 at 0.5 mg/mL). The plant extract had no effect on oxytocin-induced contractions under calcium-free conditions. Secondary metabolites belonging to classes of fatty acids, alkaloids, saponin glycosides, amino acids, limonoids, terpenes and porphyrins were identified.Conclusion: The current study reports an inhibitory effect of the plant on uterine contractility in this study, suggesting possible application as a tocolytic or as a contraceptive, as most contraceptive plants have shown uterine-relaxing effect.