Cleome viscosa L. (Cleomaceae) is an important traditional medicine of the Indian-Ayurvedic and Chinese-medicine system documented for rheumatic arthritis, hypertension, malaria, neurasthenia, and wound healing. The plant is also known as Asian spider flower and is distributed throughout the greater part of India. The present study explored the wound healing property of C. viscosa methanol extract (CvME) and its related mechanism using Wistar rat cutaneous excision wound model. Wound contraction rate, hydroxyproline quantification, and histopathological examination of wound granulation tissue were performed. The healing potential was comparatively assessed with a reference gentamicin sulfate hydrogel (0.01% w/w). Western blot for COL3A1, bFGF, and Smad-2, Smad-3, Smad-4, and Smad-7 was performed with 7-day postoperative granulation tissue. Results revealed that the topical application of CvME (2.5% w/w) significantly accelerated the wound contraction rate (95.14%, 24 postoperative days), increased the hydroxyproline content (3.947 mg/100 mg tissue), and improved histopathology of wound tissue as compared to control groups. Western blot analysis revealed that CvME significantly upregulated the expression of COL3A1 and bFGF and increased the Smad-mediated collagen production in granulation tissue. These findings suggest that C. viscosa promoted the wound repair process by attenuating the Smad-mediated collagen production in wound granulation tissue.