[Objectives]  Understanding of the molecular mechanism of interaction between Asian citrus psyllid Diaphorina citri Kuwayama and huanglongbing which is associated with Canditatus Liberibacter asiaticus (CLas). [Methods]  RNA- Seq technology was used to analyze the transcriptome of CLas infected and uninfected D. citri adults. The differentially expression genes after CLas-infection were obtained, and their functions were analyzed. [Results]  There were 1 502 unigenes that were differentially expressed between the infected and uninfected D. citri, with 764 up-regulated and 752 down-regulated in the infected psyllids. These unigenes were assigned to NCBI NR, KEGG and GO database, 1 099 unigenes had significant BlastX hit with NCBI protein database and their annotations of predicted protien were obtained. Among them, 852 unigenes were categorized into GO function categories; 931 unigenes were categorized into 239 KEGG pathways. According to the GO analysis, the unigenes which involved in metabolic process and catalytic activity function  were significantly up-regulated. Among the 53 immune-related genes which showed different express, 28 were related to the cellular immunity, 25 to the immune signaling pathway, and the up-regulated genes of these 2 groups was 64% and 32% respectively. [Conclusion]  Interaction is present between CLas and it’s vector D. citri. The metabolic activity and the immunoreaction might be affected as the related genes of these activity differently express in the CLas-infected psyllid.