The transverse relaxation rate (1/T2) of blood water protons is governed by deoxyhemoglobin concentration, therefore providing a means to determine oxygen saturation (HbO2) in vivo. However, besides CPMG inter-pulse interval of the T2 preparation and field strength, whole-blood T2 depends on sequence-specific parameters. Balanced SSFP allows for rapid image acquisition and higher in-plane resolution and thus provides an ideal readout for T2-based oximetry. Here, we quantified T2 of human blood at 1.5T for the entire range of HbO2 saturation levels using T2-prepared bSSFP sequence. The data show the expected linearity of 1/T2 with (1-HbO2)2 with the y-intercept depending on hematocrit.