The large yellow croaker (Larimichthys crocea) is the largest economically marine fish in China. P. plecoglossicida is the causative bacterium of visceral white nodules disease of large yellow croaker, which has caused huge economic losses to the cultivation of large yellow croaker. There are few studies on the host immune mechanism of large yellow croaker after P. plecoglossicida infection. In this study, the transcriptome of the spleen of large yellow croaker infected and uninfected with P. plecoglossicida was analyzed to better understand the pathogenic characteristics of P. plecoglossicida and the corresponding immune mechanism of large yellow croaker.