It is very important for spheroidic metal cobalt powders production to control the morphology of cobalt oxalate powders precursor. The spheroidic cobalt oxalate powders were prepared by conventional precipitation when a pulsed electromagnetic field (PEMF) was introduced. Scanning electron microscopy (SEM) images and X-ray powder diffraction (XRD) were used to characterize morphologies and phase structures of the cobalt oxalate powders. The research results show that a pulsed electromagnetic field (PEMF) play a key role in the process of preparation of spheroidic cobalt oxalate powders. In addition, a possible morphology control mechanism was preliminarily discussed based on the effects of PEMF on the process of growth of cobalt oxalate particles.