Introduction: Takenaka and co-workers had developed a video-enhanced microscopy technique to visualise axonal transport without staining nerves nor transporting organelles in 1980s. Their method to evaluate axonal transport is very useful but requires a special talent, a keen dynamic vision. We have recently developed another new method to quantify axonal transport with an aid of microcomputer with the open source programme, ImageJ. Method: Preparation of video clips and pretreatment on NIH Image J (1)Enhanced video images were digitized and converted to QuickTime video clips ( sampling rate, 10 Hz, duration time,120 seconds). Make video clip every 3 minutes intervals for about an hour. (2) Run ImageJ 1.46, read each video clip and rotate video image 90~180 degrees if necessary in order to fix the orientation of organelles movement from the left to the right as anterograde axonal transport direction, and the opposite direction as retrograde axonal transport. (3) 128 pixel x 128 pixel area is cropped on ImageJ, in which axonal transport is displayed appropriately. The dimension of the cropped area is fixed and adapted for all the video clips of the same experiment. (4) Subtract adjacent frame (slice) image successively in order to reduce background noise and not moving organelles. Quantification of the activity of axonal transport ( Flow analysis ) Using KBI plugin, the activity of axonal transport is quantified as the sum of particles which moves more than 3 pixels per second. The velocity of the particle is 0.1 um/s or more. Velocity vectors are calculated ( the velocity and the degree of an angle of the moving particle within a fixed area at a given resolution pixels, such as 4, 8, 16, 32 pixels). We can easily distinguish and sum up the number of anterograde transporting particles and retrograde transporting particles by the sign of an angle of velocity vector, where the former has a plus sign and the latter has a minus sign respectively. Results: Parameters of widthXy and stepXy 4 pix and greater value is suitable for the velocity calculation. With 4 pix or 8 pix value, the results from flow analysis are coincided with the results obtained from our traditional quantification method. 16 pix or more value sometimes dismissed moving particles and thus the calculated values are not consistent with our previous results. Concluding Remarks: Using NIH ImageJ with KBI plugin, the progressive movement of particles can be analyzed. Orientation, velocity, and the number of transported organelles within a fixed area are calculated easily from one video clip. (1) We define the activity of axonal transport as the sum of a particle which possesses the moving velocity more than 0.1 um/s within an limited area. (2) We suppose the velocity of particles is directly proportional to the activity of axonal transport.