A new species of the genus Cyphocaris Boeck, 1871, is described. The material examined was collected during the “Acoustics along the Brazilian Coast” (Abraços 1) project, by micronektonic trawls at a targeted depth of 525 m, off the Rocas Atoll, Rio Grande do Norte state, Brazil. Cyphocaris boecki sp. nov. can be grouped with the eyed species in the genus but differs from them—except for C. faurei K. H. Barnard, 1916 and C. latirama, Hendrycks & Conlan, 2003—in presenting a dorsally smooth pereonite 1. However, the new species can be distinguished from both by its maxilliped inner plate with two robust apical setae, pereopod 7 basis with weakly produced posterodistal lobe, telson lobes without setae, spines or apical nails, and other characters that are individually discussed among them. The new species can be readily differentiated from C. pedroi Sorrentino, Alves, Johnsson & Senna, 2016, also described from Brazil, by presenting eyes, a rounded lateral cephalic lobe, very elongated antenna 2 almost reaching body length, and pereopod 5 basis, with apically acute spur reaching about two-thirds of the propodus. This is the second record of the genus for Brazilian waters.