For biodegradable pure iron implants, a higher biodegradation rate is preferred. In this work, we compared the biodegradation of pure iron prepared by microwave sintering and laser melting (designated as MSed Fe and LMed Fe, respectively). The MSed Fe presented a distinct porous structure, while the LMed Fe presented a relatively compact structure without any obvious pores. The biodegradation rate of the MSed Fe was higher than that of the LMed Fe, and their biodegradation rates were higher than that of the as-cast Fe. The biodegradation rates of the MSed Fe and the LMed Fe were approximately 44 and 13 times higher than that of the as cast Fe, respectively. The biodegradation was closely related to the microstructure’s compactness and grain size. Moreover, the MSed Fe and the LMed Fe had satisfactory biocompatibility.