Based on a partially coherent light source, partially coherent accelerating regular triple-lobe beams are generated by imposing phase grey-scale maps on the spatial light modulator. The numerical simulation and experimental results show that there are two key factors to decide the acceleration of the main lobes of partially coherent optical accelerating regular triple-lobe beams, which are respectively the controlling parameter β of designed phase maps and the focal length f of Fourier transform lens. The relationship between β, f and the main lobes′ acceleration of partially coherent accelerating regular triple-lobe beams is also given. The results provide the mechanism of controlling ballistic trajectory of main lobes of partially coherent accelerating regular triple-cusp beams according to different research needs in the future.