We compared the effects of treatment with fluorapatite-forming calcium phosphate cement (FA-forming CPC) containing tricalcium silicate (TCS) and those of mineral trioxide aggregate (MTA), the gold standard endodontic cement, on cultured osteoblast-like cells (ROS 17/2.8 cells; ROS cells). The FA-forming CPC powder consisted of 61.29% CaHPO4, 32.26% CaCO3, and 6.45% NaF. One part TCS was combined with nine parts FA-forming CPC powder to make FA-forming CPC with TCS. A 1.5-M phosphate solution was mixed as a cement liquid with a powder/liquid ratio of 2.22. Cell culture was carried out using cell culture inserts, whereby each test material was put on a porous membrane insert in the cell culture plate. Proliferation, morphologic changes, and alkaline phosphatase activity in ROS cells were measured in the presence of FA-forming CPC with TCS and MTA and compared. The logarithmic growth phase and cellular morphologic changes in ROS cells were identical in all experimental groups. Additionally, no significant difference in alkaline phosphatase activity was noted in ROS cells exposed to FA-forming CPC with TCS and those exposed to MTA. In conclusion, FA-forming CPC with TCS has characteristics identical to those of MTA under the present experimental conditions and may thus be useful for endodontic applications.