4-Methoxyphenyl isothiocyanate (4-Methylphenyl ITC) is recognized as an antioxidant demonstrating an IC50 of 1.25 mM for scavenging DPPH free radicals. Its antioxidant capacity, as shown by the ORAC test, is 11.7 mM TE, equivalent to the efficacy of 11.7 mmol Trolox under similar conditions. Additionally, it extends the oxidation process in the Briggs–Rauscher reaction by approximately 9180 seconds. The compound also exhibits moderate cholinesterase inhibitory activity, with an inhibition rate of 30.4% for acetylcholinesterase (AChE) and 17.9% for butyrylcholinesterase (BChE). Research suggests 4-Methoxyphenyl isothiocyanate holds promise for applications in antioxidant and neurological disorder studies.