The invention provides a gene chip detection method for a classical swine fever virus (CSFV), a porcine circovirus virus type 2 (PCV-2), a porcine reproductive and respiratory syndrome virus Europe type (PRRSVE) and a porcine reproductive and respiratory syndrome virus America type (PRRSVA). A gene chip is shown as a probe sequence in the table of the specification. The invention discloses a method for simultaneously detecting three diseases, namely classical swine fever (CSF), a porcine circovirus type 2 (PCV-2) and a porcine reproductive and respiratory syndrome (PRRS) by using the gene chip. By the method, the problems that the conventional detection technology is time-consuming and labor-consuming and has low specificity, or only can be used for detecting a single disease are solved. All probes provided by the invention are synthesized into a connecting amino group at a 5' end, a poly T connecting arm with the length of 15 bp is provided, and a result shows that fixing efficiency is relatively high. By a polymerase chain reaction (PCR) amplification technology with mark primers, various kinds of fluorescent mark deoxyribonucleic acid (DNA) complementary to corresponding probescan be amplified at a time, and the high specificity and sensitivity of nucleic acid hybridization in a solid-liquid phase can be ensured. In addition, by a mark method, detection time is greatly shortened, the cost of chip detection is lowered, and the detection method is more suitable to be popularized in clinical application.