Methicillin-resistant Staphylococcus aureus (MRSA) is a prevalent and highly virulent bacterium encountered in clinical settings. Due to its uneven drug resistance profile and the multitude of factors influencing detection rates, precise and sensitive identification of MRSA is essential. Herein, we developed a detection system (called “APC-Cas-PLNPs”) that can ultra-sensitive detection for MRSA, using nucleic acid-based allosteric probe, CRISPR-Cas12a and dual-colored persistent luminescent nanoparticles tandem detection. Simply, allosteric probe was used for specifically recognize MRSA and cyclic signal amplification, and then initiated catalytic CRISPR-Cas12a collateral cleavage. Meanwhile, red-emitting ZnGa2O4:Cr (ZGC) bonded with BHQ3 modified single-stranded DNA to create a detection probe known as ZGC@BHQ3, and green-emitting Zn2GeO4:Mn (ZGM) was utilized as the reference probe and electrostatically bound to both probes, forming the ratiometric luminescence sensor ZGC@BHQ3-ZGM for CRISPR-Cas12a detection.With this strategy, the non-nucleic acid targets were dexterously converted into fluorescent signals. This tandem detection system eliminates interference from background fluorescence and external factors, and provided a novel signal amplification and conversion strategy, which enables accurate and sensitive quantification of MRSA (1-105 CFU/mL) without requiring isolation and DNA extraction. Moreover, APC-Cas-PLNPs can recognize low levels of MRSA in food samples such as milk and orange juice, as well as in mouse serum, demonstrating greater sensitivity compared to real-time PCR. This method holds significant potential application value in food detection and early diagnosis of pathogenic bacteria, highlighting its broad applicability.