【Objective】 To investigate the influence of different packaging methods on the volume of low-dose(0.5 U) suspended leucocyte depleted red blood cells(SLD RBC) and provide reference for accurate labeling. 【Methods】 Bags of SLD RBC in 1.5 U and 2 U were randomly sampled to measure the weight and specific gravity of each bag, so as to estimate the blood volume.The relationship between the weight and volume of 0.5 U blood, split from different parent bags, was analyzed and the linear regression equation was put forward.The regression equation was used to calculate and analyze the difference in the volume of 0.5 U SLD RBC prepared by three different packaging methods (A: manual multi-bag average packing; B: instrument multi-bag average packing; C: manual single-bag packing) in actual work. 【Results】 The specific gravity of 1.5 U (38 bags) and 2 U SLD RBC (39 bags) were (1.090±0.011) g/mL and (1.097±0.013) g/mL, respectively, and the difference was statistically significant (P<0.05). After the 0.5 U subsidiary bags were split from the parent bags(1.5 U or 2 U), the regression equations for the volume (Y) of 0.5 U and gross weight (X) of the whole bag were respectively: Y1.5 U packing=0.902 7X-12.52 (P<0.05) and Y2 U packing=0.905 6X-13.15(P<0.05). In actual blood packaging, the average blood volume of 0.5 U subsidiary bags split from 1.5 U bag, using method A and B, were smaller than those split from 2 U bag [(62.12±5.38) mL and (62.50±6.77) mL vs (67.72±3.81) mL and(68.39±6.44)mL] (P<0.05), with the deviation of low-dose blood volume from 5.593 mL to 5.887 mL.The volume deviation by method B (10.84% and 9.42%) were greater than that by method A (8.67% and 5.63%). The average volume of 0.5 U subsidiary bags split from 1.5 U and 2 U by method C were (65.49±1.72) mL and (64.99±1.91) mL (P>0.05), with volume deviation at 2.63% and 2.94%, respectively.The mean volume value of overall 0.5 U blood (n=483) was (65.35±5.34) mL. 【Conclusion】 For packaging 0.5 U subsidiary bags, the instrument multi-bag packaging showed the largest volume deviation, followed by the manual multi-bag packaging and the single-bag packaging.The volume labeling of low-dose SLD RBC should be established, according to the specifications of parent bags and specific gravity.