Joseph Julius Kustus (September 5, 1882 – April 27, 1916) was a professional baseball outfielder for the 1909 Brooklyn Superbas.

He had a short career as a professional baseball player because he debuted April 17, 1909 and his last game was July 10, 1909.

[2] Joseph "Jul" died in the Eloise Sanitarium in Nankin Township, Michigan April 27, 1916 of pulmonary tuberculosis.

[2] He never married but had a relationship with a woman named Rose Ann Zimmeth and they were business partners in a Detroit grocery.

He was survived by a brother August who also died of tuberculosis in 1917 and two sisters Mrs. Julia Sabatini and Mrs. C. French, and two half-sisters Annie Lukaszek and Elizabeth Kozlowski.