Ultrasound computed tomography (USCT) is a 3D imaging tool, especially for breast screening. Sound-speed tomography as one imaging modal of USCT is widely studied by researchers because of its great clinical potential for early breast cancer detection. Sound-speed reconstruction methods include ray-based methods and wave-based methods. In this study, a ray-based method for sound speed reconstruction: Fresnel volume tomography (FVT) is implemented. We use Limitedmemory Broyden–Fletcher–Goldfarb–Shanno (L-BFGS) optimization algorithm to solve the large and sparse equation for the inversion step. Considering the great computation burden in the L-BFGS inversion process, two kinds of acceleration schemes: CPU parallel and GPU parallel schemes are used and evaluated by in vitro experiment. The corresponding acceleration ratios are 5.3 and 18.6 for the 512×512 sound speed image reconstruction, compared to CPU serial computation.