The invention discloses a method for measuring the mixing uniformity of tobacco shreds of cigarettes, comprising the following steps: (1) selecting expanded tobacco shreds as tracers; (2) sampling; (3) separating; (4) drying; and (5) calculating the mixing uniformity. The use of the expanded tobacco shreds as the tracers has the following advantages that 1, the particle size and the distribution uniformity of the expanded tobacco shreds have little difference from other tobacco shreds, thus the expanded tobacco shreds can well represent the motion of the integral body, and can be used as the tracers; 2, the expanded tobacco shreds are one of common raw materials of a cigarette formula, and most cigarette formulas contain more than 3% of the expanded tobacco shreds; and 3, the expanded tobacco shreds have much smaller density than leaf shreds, stem shreds and papermaking sheet tobacco shreds, thus the expanded tobacco shreds can be completely separated by using the density difference through floating method. The separation solution used in the invention is a non-polar solution, thus the density changes of the components of the tobacco shreds caused by the intersolubility of the separation solution and the water in the tobacco shreds are avoided. The method has high measuring precision, and the precision is 0.08-0.66 %.