We developed a new detection method to solve various problems existing in current detection technology. In our experiment, gene fragments with different hairpin structures were modified with colloidal gold, and different gene fragments were targeted to different mirnas. After binding with mirnas, HCR isothermal amplification reaction was triggered. At the same time, the reverse cutting function of CRISPR technology is used to release fluorescence signals to complete miRNA detection. This project will establish a specific detection method of miRNA by combining the function of colloid gold technology, HCR constant temperature amplification technology and CRISPR reverse cutting, and predict whether patients have myocardial infarction according to the detection results. Finally, the test strip is made, and the sample drops are added to it to show whether the patient suffers from AMI, which is convenient to use, fast and simple. Overall, myocardial infarction testing methods around the world have advantages and disadvantages in different situations. As medical technology continues to advance, our methods will be more accurate and safer. To provide better support for clinical diagnosis and treatment.