Background: Reduced range of motion can affect the person’s ability to carry out everyday activities and can lead to secondary problems such as strain, discomfort, contractures and deformities. The calf muscle considered one of the anti-gravity muscles. Isolated gastrocnemius equines contracture has been associated with several foot and ankle pathologies Aim of the study: this study aimed to assess the flexibility of calf muscle (gastrocnemius and soleus), detect the difference in muscle flexibility between boys and girls and identify differences in calf muscle flexibility between dominant and non-dominant lower limbs. Methods: For this purpose, 60 normally developed children participated in this study, they were divided into two groups, group A (30 boys) and group B (30 girls). They all assessed by footedness tasks (foot preference) to identify dominant and non-dominant lower, manual assessment of gastrocnemius and soleus flexibility by Silfverskio¨ test and electro goniometer used to record the angles of gastrocnemius and soleus for both groups Results: The study findings, revealed a statistically non-significant differences in muscle flexibility between group (A) and group (B). Significant differences in muscle flexibility between dominant and non-dominant (p <.05).