In this Letter,we present B-scan-sectioned dynamic micro-optical coherence tomography[BD-MOCT]for high-quality sub-cellular dynamic contrast imaging.Dynamic micro-optical coherence tomography[D-MOCT]is a functional optical coher-ence tomography[OCT]technique performed on high-resolution[micron level]OCT systems;hundreds of consecutive B-scans need to be acquired for dynamic signal extraction,which requires relatively long data acquisition time.Bulk motions occurring during data acquisition[even at the micron level]may degrade the quality of the obtained dynamic contrast images.In BD-MOCT,each full B-scan is divided into several sub-B-scans,and each sub-B-scan repeats multiple times before the sample beam moves to the next sub-B-scan.After all of the sub-B-scans for a full B-scan are completely acquired,we stitch all of the sub-B-scans into the same number of full B-scans.In this way,the time interval between two consecutive stitched B-scans could be reduced multiple times for bulk-motion suppression.The performed scanning protocol modulates the scanning sequences of fast scanning and repeat scanning for improving the dynamic contrast image quality,while the total data acquisition time remains almost the same.