Abstract: A method based on direct analysis in real time (DART) ion source combined with electrostatic field Orbitrap high resolution mass spectrometry (Orbitrap HRMS) was developed to rapidly screen and confirm 22 chemical sunscreens in cosmetic. Chemical sunscreens in cosmetic samples were extracted with methanol-tetrahydrofuran-water mixture (25:45:30, V/V/V), and the extracts were diluted with 80% methanol. The aliquot (2 μL) extract solution was added to the tip of quartz glass rod and determined by DART-Orbitrap HRMS. The sample transmission speed of the injection module was set at 0.5 mm/s. The DART ion source was operated under helium reaction mode with an ionization temperature of 500 ℃ and a grid voltage of 400 V. The distance between the ion source outlet and the mass spectrometry inlet was set at 3.0 cm. The HRMS was conducted using a full-scan and data-dependent acquisition mode for both positive and negative ions simultaneously. The primary scanning range was m/z 120-900, the resolution was 70 000, and the temperature of ion transmission tube was 320 ℃. The method validation demonstrates excellent specificity with high sensitivity and no interference from cosmetic matrices. The limits of detection (LODs) of 22 sunscreens are 0.04-4 μg/g. In the analysis of actual samples, ethylhexyl methoxycinnamate shows the highest detection frequency. Among 15 batches of tested sunscreen products, 3 batches fail to detect the labeled sunscreens, while the remaining samples contain 1 to 6 chemical sunscreens. In the analysis of 6 batches of cosmetic products, ethylhexyl methoxycinnamate is detected in 3 batches. The detection results are consistent with those obtained by high-performance liquid chromatography (HPLC). Firstly, the mass spectrometry conditions were optimized, including the determination of the acquisition mode and the selection of the optimal collision energy. It was found that camphor benzalkonium methosulfat had a different fragmentation pattern from that of other substances, of which a methyl sulfate radical was removed, following the breaking off of a methylene group. Then, the DART ion source parameters were optimized, including the ionization temperature, injection transmission speed, and grid voltage, while the spotting volume was also investigated. Furthermore, the pretreatment methods were investigated, including extracting solvent and diluting solvent. The results showed that the addition of perchloric acid has little effect on the extraction efficiency, and the response of dilution solvents such as methanol, ethanol, tetrahydrofuran and 80% methanol was compared. Considering the instrument response, peak shape and environmental friendliness, 80% methanol was selected as the dilution solvent. Finally, the LODs of this method were compared with those of different methods such as HPLC, LC-MS/MS and GC-MS, which showed that the DART-Orbitrap HRMS has the advantages of rapid screening of 22 sunscreens and low detection limit. In conclusion, the established method provides easy, quick, accurate analysis of chemical sunscreens in cosmetics with minimal environmental impact, making it ideal for rapid screening and confirmation.