<p class="Abstract">The primary objective of the current work was to investigate the antitumor potential of <em>Primula macrophylla</em> extracts in human colon cancer cell line (Colo-205) along with evaluating the effects on apoptosis induction, cell cycle arrest and mitochondrial membrane potential. Cell viability was assessed by tetrazolium-based MTT assay. Flow cytometry measurement was carried out to assess the effect of the extract on cell cycle phase distribution and mitochondrial transmembrane potential. Results showed that <em>P. macrophylla</em> methanol extract was effective and exhibited highest cell growth inhibition (IC<sub>50</sub> value, 26.17 μg/mL). Methanol extract significantly increased the side-scattering profile of Colo-205 cells in concentration-dependent pattern. Exposure of Colo-205 cells with different concentrations of the methanol extract (0-80 μg/mL) caused dose-dependent G0/G1 cell cycle arrest along with inducing apoptotic cascade by increasing the population of cells at G0/G1 phase. Furthermore, methanol extract treatment caused an increase in mitochondrial membrane depolarization in Colo-205 cells.</p><p class="Abstract"><strong>Video Clip of Methodlogy</strong> (3 min 17 sec): <a href="https://youtube.com/v/yy-rCjDN830">Click</a> <a href="https://youtube.com/watch?v=yy-rCjDN830">If failed</a></p>