Abstract Broken kernels are among the by-products of processing cashew nuts which have less commercial value. The present work aimed to obtain a cashew kernel protein concentrate from broken kernels, and then characterize it as well as using it in a vegetable burger formulation. The concentrate was obtained by isoelectric precipitation at four different pHs and subsequent drying. Higher yield was 58.6% of proteins (pH 4.0 and 4.5). The concentrate showed Water Absorption Capacity (WAC) of 1.85 mL/g and Oil Absorption Capacity (OAC) of 1.06 mL/g, as well as low solubility in aqueous medium and low foaming capacity. The concentrate was used in vegetable burger production as a substitute for soybean protein. The burgers were submitted to sensory evaluation and obtained an average of 6.6 on a nine-point scale, thus being within the acceptance zone. Regarding the purchase intent, 60% of the judges would probably or would certainly buy the product. Therefore, the cashew kernel protein concentrate can be used as a protein ingredient for food formulation. Producing cashew kernel protein concentrate allows the use of broken kernels generated in the cashew nut industrial process.