This research article focuses on the pathway for metal‐free unprecedented one‐pot three‐component synthesis of biologically active 3‐pyrazolyl‐thiazolidin‐4‐one derivatives through cyclo‐condensation of aromatic aldehydes, 1H‐pyrazol‐3‐amine and thioglycolic acid in aqueous medium. p‐Toluene sulphonic acid (PTSA), a non‐toxic, cheaper, easily accessible, eco‐benign, organic acid‐catalyst was explored to mediate this reaction. Formation of novel 3‐pyrazolyl‐thiazolidin‐4‐one derivatives, environment‐benign conditions, quick reaction time, excellent functional group acceptance and moderate to high yield of the products are some of the chief advantages of the reaction. Further, this methodology will surely contribute in various fields of synthetic organic methodology, pharmaceutical industry and natural bio‐active product synthesis.