Abstract: Cleruchoides noackae (Hymenoptera: Mymaridae) is the most promising biological control agent against Thaumastocoris peregrinus, the bronze bug, which is a pest of eucalyptus. Nevertheless, plant extracts may also be a viable option in an integrated pest program. Thus, it is important to assess possible harmful effects that these extracts might have on the parasitoid. Therefore, this work aimed to verify the effect of 5% aqueous extracts of Matricaria chamomilla, Maytenus ilicifolia and Echinodorus grandiflorus on the development of C. noackae. For that, Thaumastocoris peregrinus eggs were offered to C. noackae to parasitize, divided in two groups, and treated after one and seven days with the plant extracts. There was no statistical difference between the treatments and the control group regarding parasitoid emergence in none of the tests. However, there was an increase in egg viability and number of emerged parasitoids when comparing the eggs treated one and seven days after parasitism for all the treatments. In conclusion, none of the plant extracts caused any harmful effect on C. noackae early development.