The present invention relates to subterranean well cementing operations, and more particularly, to cement compositions having improved corrosion resistance and methods of using such compositions in subterranean formations. The cement compositions generally include an unhydrated cement that includes a high alumina cement, a silica source, and a soluble phosphate; and a set retarder that includes a water soluble carboxylic acid. Optionally, other additives may be included, such as accelerants, dispersants, weighting agents, and the like.