Siddha is one of the traditional medical systems of India; previous ethnobotanical survey in Virudhunagar district indicated a high consensus for treating musculoskeletal ailments.This study was aimed to quantitatively document the medicinal plants used to treat musculoskeletal ailments by non-institutionally trained siddha practitioners of Virudhunagar district, Tamil Nadu, India.This work was the outcome of free-list interviews conducted among 45 informants between April 2016 and January 2017. Sampling sufficiency was assessed by plotting Shannon-Wiener's index and cumulative number of UR. Informant consensus was assessed using Informant Consensus Factor (F) and Informant Agreement Ratio (IAR).This study recorded the data regarding 116 plant species which were used to prepare 129 formulations; analysis of the data yielded 490 UR. Among these, 65.3% of UR dealt with internal applications and 34.6% dealt with external applications. In the case of internally used formulations, pain and general musculoskeletal ailments had high F values. In the case of externally used formulations, headache and pain had high F values.Important species prescribed by the informants to treat various musculoskeletal ailments were: Azima tetracantha, Ricinus communis, Sesamum indicum, Moringa oleifera, Cardiospermum halicacabum (internal application), Calophyllum inophyllum, Justicia adhatoda, Curcuma longa, Calotropis gigantea, Zingiber officinale, Withania somnifera, Strychnos nux-vomica, Dodonaea viscosa (external application), Azadirachta indica, Clerodendrum phlomidis,Delonix elata, Pergularia daemia and Vitex negundo (internal and external applications). Robust studies on these local claims will help to improve the community healthcare and will yield some novel agents to treat musculoskeletal ailments.