The invention provides a method for improving the concentration of a pipeline transportation coal water slurry end product. The method includes the steps of: (1) mixing part of pipeline transportation coal slurry with water and an additive, and performing fine grinding to obtain a first slurry; (2) mixing part of pipeline transportation coal slurry, part of a first slurry, water and an additive, and performing fine grinding to obtain a second slurry; (3) mixing the remaining first slurry with the second slurry to obtain a third slurry; (4) mixing raw coal with the remaining pipeline transportation coal slurry, part of the third slurry, water and the additive, and then performing wet ore grinding to obtain a fourth slurry; and (5) mixing the fourth slurry with the remaining third slurry, and carrying out screening and impurity removal, thus obtaining a finished coal slurry product. The method provided by the invention can optimize coal slurry granularity grading, and improves the concentration by at least 8-20% compared with the pipeline transportation end product. And the coal slurry fluidity, stability and atomization performance are all greatly improved.