The adverse effects of high temperature stress can be alleviated by thermotolerance induced by exogenous application of plant growth regulators or by gradual application of temperature stress. Physalis peruviana L., commonly known as the Cape gooseberry, is a source of a variety of phytocompounds such as withanolides (withanone, withaferin A, and withanolide A). These withanolides are potentially high-value drug candidates because of their various pharmacological properties. The production of withanolides via traditional agriculture is commercially inadequate. In the present study, elicitation strategies were employed to improve the crop's thermotolerance and accumulation of withanolides. For these purposes, the effects of heat acclimation (45 °C HA) or salicylic acid (150 mM SA) treatments in inducing withanolide production and thermotolerance were tested in leaves of P. peruviana L. grown under high temperature stress (55 °C). Considerable increases in the production of withanolides (up to 86.83 mg g?1 dry weight, dw) were observed when the cultures were exposed for 5 h to high temperature stress after pretreatment with SA. SA application and heat acclimation increased the activity of superoxide dismutase (SOD; EC 1.15.1.1) and decreased the catalase activity (CAT; EC 1.11.1.6). Both SA and heat acclimation caused a significant increase in endogenous H2O2 and proline content. Changes in related antioxidants paralleling heat acclimation or SA treatment suggest that common mechanisms might be involved in thermotolerance induced by SA and heat acclimation.