Cotesia plutellae as an endoparasitoid wasp is the natural enemy against the diamondback moth, Plutella xylostella. For successful parasitism of the offspring, the female parasitoid always injects venom with other parasitic factors such as polydnavirus, teratocytes and ovary proteins. These venom products prevent their eggs from host immune system as well as modulate their host. To identify of constituents of venom in relation of host-parasitoid interaction, total RNA of the venom gland were extracted and analyzed with RNA-seq. RNA-seq reveals that 5.5 Gbp were read and approximately 3322 transcripts were identified. The transcripts related to the biological process, cellular components and molecular functions occupied about 20%, 15% and 18%, respectively. Among these transcripts, 301 genes were related to the immune activities such as calreticulin, defensing, phosphatases and serpin etc. These results suggest that some proteins exhibiting biological function related to the immune response can be contribute to the development of wasp in the host.