The increasing global popularity of traditional Chinese medicines (TCMs) raises significant concerns about potential contamination with organophosphorus pesticides (OPs). Portable analytical methods are particularly valuable for on-site pesticide analysis, enabling rapid screening and enhancing the safety assurance of TCM products. This study investigates the use of miniaturized microplasma atomic emission spectrometry (AES) as a promising tool for methyl parathion (MP) analysis in TCMs, leveraging the inhibition effect of OPs on butyrylcholinesterase (BChE) within a gold filament enrichment coupling point discharge chemical vapor generation atomic emission spectrometry (PD-CVG-AES) system. Specifically, BChE catalyzes the hydrolysis of acetylthiocholine chloride (ATCh) to form thiocholine (TCh), which contains sulfhydryl groups (-SH) that can strongly bind with Hg2+, leading to less efficient vapor generation and reduced AES signals of Hg2+. However, OPs like MP inhibit BChE activity and suppress TCh generation, resulting in the recovery AES signals. Ultra-trace levels of MP can be indirectly detected due to the high sensitivity of Hg2+ analysis using the gold filament enrichment PD-AES system. Under optimal conditions, the limit of detection (LOD) for the MP assay was 13 ng mL-1 within a range of 0.5 to 10 μg mL-1, with a relative standard deviation (RSD, n=5) of 0.8%. This analytical approach has proven effective in the detection of MP in TCMs, with advantages including ease of use and affordability.