In this article, the design of a fully 3D-printed bull-eye dielectric leaky-wave antenna is presented. The antenna replaces the concentric metallic rings of a traditional bull-eye implementation with rings made with high-permittivity dielectric filaments. This introduces two extra degrees of freedom in the design, namely the permittivity of the rings and their height. The effect of these two new parameters in the antenna performance is studied. Simulation results show that the proposed antenna maintains the cylindrical leaky-wave mode behavior, generating a conical beam pattern depending on the operating frequency. Finally, the antenna was successfully 3D-printed using a low-cost 3D-printer and commercially available dielectric filaments with the required relative permittivity values.