Three groups of cross-shaped terahertz band-pass filters with different central frequencies are designed by using the finite difference time domain method. A femtosecond laser micro-machining system is built and the substrateless terahertz filter on a single-layered aluminum foil is fabricated. The transmissivities of these band-pass filters are tested by using the time-domain terahertz spectroscopy system. The experimental results are in a good agreement with the simulated results. All the transmissivities at central frequencies of these filters are over 85%, which reaches the commercial level of terahertz filters.