Both the electrochemiluminescence (ECL) method for sensitive detection of ozone and the ECL resonance energy transfer (ECRET) using ozone have been reported for the first time. It is based on the ECRET of Ru(phen)3(2+)-doped silica nanoparticles (RuSiNPs) to indigo carmine. In the absence of ozone, the ECL of RuSiNPs is quenched as a result of the ECRET of RuSiNPs to indigo carmine. In the presence of ozone, the ECL of the system is "turned on" because ozone can oxidize indigo carmine and interrupt the ECRET from RuSiNPs to indigo carmine. In this way, it provides a simple ECL sensing of ozone via the proposed RuSiNP-based ECRET strategy with a linear range from 0.05-3.0 μM and a limit of detection (LOD) of 30 nM. The detection takes less than 5 min. This method is also successfully applied in the analysis of ozone in human serum samples and atmospheric samples.