Background Human immunodeficiency virus (HIV) is infecting over 34.0 million people worldwide, being responsible for one of the major current pandemics [1]. The most severely affected region is the Sub-Saharan Africa where nearly 1 in 20 adults is infected with HIV, accounting for 69% of infections worldwide [1]. Several strategies to halt HIV spread are currently being pursued, including the use of ectopic microbiocides. This approach is particularly important for women, among which the infection rate can be almost three more times than men. CyanovirinN (CVN) is a lectin-like protein isolated from blue algae Nostoc ellipsosporum. CVN is highly thermo stable and is capable of binding to HIV GP120 protein blocking viral infection [2,3]. In this report we describe the use of transgenic soybean plants as a potential platform to achieve large scale, cost-effective production of CVN.