Males continue to dominate mathematics-related areas in graduate school and employment, possibly due to the differential guidance that they receive as students. In the present study, 180 undergraduates completed an online survey on the career and graduate school guidance they received from mathematics professors. Student sex, professor sex, and help-seeking behaviors were considered as possible correlates of career guidance. Students of both sexes reported similar help-seeking behaviors, but males received more career guidance from professors. Help-seeking levels along with an interaction term of student sex and professor sex significantly predicted career guidance. The influence of student sex on career guidance depended on professor sex. Male students with male professors received the greatest amount of career guidance. The differential career guidance may contribute to the pervasive sex gap within the mathematics field.