Aims and objectives:This study aimed to analyze immunohistochemically the density of myofibroblast (MF) in dentigerous cyst (DC), odontogenic keratocyst (OKC) and ameloblastoma (AB). Methods: Thirty formalin-fixed, paraffin-embedded specimens of DC, OKC and AB, ten each, were included in the present study. Immunohistochemical staining with anti-α-SMA primary antibody was performed. Area fraction of immunopositivity was measured by image analysis software followed by statistical analysis using Kruskal Wallis and posthoc Dunn's tests. Results: All cases of the three lesions were immunopositive for α-SMA. The median area fractions were 0.57, 8.72 and 17.87 for DC, OKC and AB respectively with a statistically non-significant difference between AB and OKC and statistically significant differences between AB and DC and between OKC and DC. A positive correlation was observed between the density of MF and the known biologic behavior of the lesions. Conclusion: Over-expression of α-SMA found in AB and OKC might be used as a reliable marker for aggressiveness.