The effects of experimental conditions such as restraint states, water losing conditions and sample thickness on the plastic shrinkage cracking of cement mortar were investigated. The results show: (1) different restraints, such as increasing steel restraint or without steel restraint, placing restraints in the middle of and at the top of the specimen, and quasi free state, have different effects on the plastic shrinkage cracking. (2) The water losing conditions, such as different trowel manners, sprinkling water, environmental temperature and relative humidity, also have different effects on the plastic shrinkage cracking. (3) With the increase of the thickness of the mortar, the total cracking weighted value decreases. Concrete has higher resistance to the plastic shrinkage cracking than mortar.