A disk brake device has a fixing member, a housing, two brake pads, a driving assembly, and a pushing element. The driving assembly is mounted on the housing and has an axle, a driving arm, a driving disk, a pushing disk, multiple driving elements, and a spring. The driving disk is mounted securely on and around the axle. The pushing disk is mounted rotatably on and around the axle. Each of the driving disk and the pushing disk has a side facing each other and multiple guiding recesses defined in the side. Each guiding recess has a deep end and a shallow end. The driving elements are held respectively in corresponding guiding recesses. The pushing element is mounted between the driving assembly and the fixing member and abutting against one of the driving assembly and the fixing member.