We use the location of stellar sequence in color-color diagrams as a tool to estimate the accuracy of our photometric zero-point across the survey field.  We choose stars brighter than i=22.5 from the HSC data and compare the observed location of the stellar sequence with that expected from a stellar library of  Pickles (1998).  We estimate both the scatter and offset of the sequence on a patch by patch basis.  The scatter plot (left) shows the spatial distribution of the stellar sequence scatter for a given color combination. The color bar on the right indicates the amount of the scatter.  The gray rectangles are the tract borders and the tract IDs are also indicated.  The offset v1 plots (middle) are the zero-point offsets.  In some regions, a clear difference between the i and i2 band photometry can be seen (e.g., Wide-Autumn: XMM-LSS).  The zero-point offsets as well as the r/i vs r2/i2 differences can be corrected for  (see Section 3.8 and 3.9 of the PDR3 paper), and the right plot (offset v2) shows the stellar sequence offsets after these corrections are applied.  The offsets are significantly reduced over the entire survey field.