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Stand-off Raman spectroscopy combines the superior advantages of both Raman spectroscopy and remote detection to retrieve molecular vibrational fingerprints of chemicals at inaccessible sites. However, it is currently restricted to the detection of pure solids and liquids and not widely applicable for dispersed molecules in air. Herein, we realize real-time stand-off SERS spectroscopy for remote and multiplex detection of atmospheric airborne species by integrating a long-range optic system with a 3D molecular trapping metal-organic framework (MOF)-integrated SERS platform. Formed via the self-assembly of Ag@MOF core-shell nanoparticles, our 3D plasmonic architecture exhibits micrometer-sized thick hotspot to allow active sorption and rapid detection of aerosols, gas and volatile organic compounds down to parts-per-billion level, notably up to 10 meters. The platform is also highly sensitive to changes in atmospheric content as demonstrated in the temporal monitoring of gaseous CO2 in several cycles. Importantly, we demonstrate the remote and multiplex quantification of polycyclic aromatic hydrocarbons (PAH) mixtures in real-time under outdoor daylight. By overcoming core challenges in current remote Raman spectroscopy, our strategy creates enormous opportunity in the long-distance and sensitive monitoring of air/gaseous environment at the molecular level, especially important in environmental conservation, disaster prevention and homeland defense.