Accurate total and differential cell counts are essential for cell therapy production. The morphological parameters of NK cells for membrane integrity, phosphatidylserine exposure, cytosolic fragmentation serves as powerful predictors of viability and cell count. NK cells were serially diluted to triplicate and perform cell count through Flow Imaging Microscopy (FIM) method by flow cam validating the procedure with cell counter and FACS. Training software filter was generated referenced from the parameters from cell counter and FACS like cell size and circularity. Optimized software filter for live cell, dead cells and debris investigation cell viability and cell count was perform to carry the linearity and precision study. Particle size distribution and Suspension of cell characterization were followed to distinguish the cell type which is important criteria for the cell experiment. Media particles count showed significant result to claim the media must be filtered before every cell test. Cell viability of NK cell was determined by FIM. Coefficient of determination (R2) for linearity were found to be >0.999 and 0.97976 in FIM and cell counter respectively. While Coefficient of variation for precision were found to be 1.607 % and 13.8 % in FIM and cell counter respectively. Applying the ISO 20391-2:2019 Biotechnology – Cell Counting – Part 2, cell count was performed. Linearity and precision confirmed that flow cam as flow imaging technology can be use as more authenticate and powerful tools for morphological cell count if software filters are well verified and documented.