We propose to clarify magnetic properties of Ca-doped Nd227 pyrocholore ruthenates, (Nd1-xCax)2Ru2O7., by changing the Ca concentration. The Ru spin forms a long-range ordered state for x=0 and the magnetic transition temperature is being suppressed with increasing the carrier concentration. A quantum critical point where the magnetic ordered state disappears is suggested to exist around x~0.20. We aim to determine the carrier doping dependence of a long-range ordered state of Ru spins clarifying a magnetic phase diagram of this system. We try to investigate the change in the Ru spin against the carrier concentrationin conjunction with density functional theory calculations in comparison with the results obtained in the Nd227 irridate.