Cheese pizzas fortified with casein phosphopeptide (CPP) and calcium were subjected to an in vitro digestion to assess whether CPP could prevent the precipitation of calcium. The total calcium content of the cheese pizzas was adjusted to 1,000 mg per pizza (∼370 g) with the addition of calcium originating from eggshells. Two levels of trypsin-digested caseins (367 and 459 mg), with a CPP content of ∼20%, were added to each pizza. The in vitro digested pizzas were then centrifuged and the supernatant was mixed with Na₂HPO₃ at 37℃ to estimate the possible soluble effect of CPP on calcium. After 24 h of reaction, the solution was centrifuged and the calcium content in the resultant supernatant was analyzed by inductively coupled plasma-atomic emission spectroscopy. One-way statistical analyses showed that CPP had a positive effect on the solubilization of calcium against phosphate (p<0.05). Cheese pizza supplemented with 459 mg of CPP powder was able to prevent precipitation of calcium by 98.8%, whereas no CPP-added cheese pizza solubilized 86.4% of the calcium. A sensory test was also carried out, revealing that panelists could not discern the bitter taste of the CPP added to the pizzas.