Recently, deuterium oxide (D2O) has been proposed as an alternative contrast agent on rodent brain perfusion by monitoring the attenuation of 1H signal. Since D2O is a highly diffusible contrast agent, the revealed information of Gd chelates and D2O are different. In this study, we aimed to re-investigate the perfusion information carried by D2O with advanced spatial resolution. We speculated that D2O slowly diffused into tumor area and continuously exchanged with tissue water until a balanced concentration. Inside the tumor region, the heterogeneity shown by D2O and Gd-DTPA are somewhat different.