The cotton boll weevil (Anthonomus grandis) and the fall armyworm (Spodoptera frugiperda) are considered key pests in the cotton crop, causing severe damages in worldwide production. The use of Bacillus thuringiensis  endotoxins to control these insect arises as an efficient alternative of control. Its crystalline inclusions formed during sporulation, composed by delta-endotoxin, present specific toxicity against the insects and are harmless to humans. Aiming to identify specific toxins to A. grandis, we have characterized a Brazilian Bt strain. Biochemical and electronic microscopy characterization showed the presence of spherical and bipyramidal crystals composed with proteins of 130 and 70 kDa. By using primers for cry genes we cloned three genes identified as cry1Ab, cry1Ia and cry8. The Cry1Ia had 99% identity with other described Cry1Ia proteins and Cry8 toxin shows 68% of identity with other Cry8 protein group. The Cry8 toxin show lower identities, suggesting be a novel toxin with different insecticide specificity. Both cry8 and cry1Ia genes were expressed in an Escherichia coli system and bioassays with recombinant-proteins showed activity towards A. grandis and S. frugiperda.  These new genes isolated represent a great potential to be used in genetic improvement program of cotton crop to A. grandis and S. frugiperda control.  Novel specificities based on the sequence of the new cry8 and cry1Ia12 genes can be explored by the use of techniques such as DNA shuffling.