<p>Food safety concerns everyone, and <i>Staphylococcus aureus</i> is a common foodborne pathogen with a complex and slow detection process. To improve the detection speed and accuracy of pathogenic bacteria in fresh meat products, a dual-signal composite rapid detection system consisting of upconversion fluorescence detection and magnetic nano detection is developed. When the ratio of upconversion nanomaterials to magnetic conversion nanomaterials was 10:9, the processing time of the detection system was 20 min. When the stabilizer was added to the detection system, the detection accuracy reached more than 90%. The designed method took the shortest detection time, taking only 1 day to complete, while the traditional plate counting method took 5 days and the nano rapid detection method took 2 days. When the detection system designed for the study detects <i>Staphylococcus aureus</i>, the detection accuracy was similar to that of the traditional plate counting, with a relative standard deviation of less than 10% and could be reduced to around 3%. In this paper, a rapid detection system for dual-signal composite is developed based on upconversion fluorescence and magnetic nanomaterials. When the concentration was 1 × 10³, the detection concentration, recovery rate, and detection time of the designed method were 0.95 ± 0.02 × 10³&#xa0;CFU/mL, 95%, and 1&#xa0;day, respectively. However, under the same conditions, the nano rapid detection method had a detection concentration, recovery rate, and detection time of 0.91 ± 0.04 × 10³&#xa0;CFU/mL, 91%, and 2&#xa0;days, respectively. The designed method is superior to existing methods on detection concentration, recovery rate, and detection time. The <i>Staphylococcus aureus</i> detection system effectively accelerates the detection speed of fresh meat products while ensuring detection accuracy.</p>