Size distribution of glutenin macropolymer(GMP) particles significantly affects the quality of final products in wheat. Six wheat varieties in eastern China were used for investigating the GMP content, particle size distribution and their relation. The results showed that the particle diameter of GMP changed from 0.38 μm to 269 μm. A typical bimodal curve of volume distribution of particles with peak values ranged from 4.44 μm to 5.36 μm and from 45.76 μm to 116.30 μm, respectively. Number distribution of particles showed the typical population with peak values in the range of 0.57-1.00 μm. Proportions of granules <12 μm, 12-80 μm and >80 μm were in the range of 17.1%-47.8%, 32.1%-50.3% and 10.2%-38.1% of total volume, respectively. The content of GMP was negatively correlated with the volume of GMP particles <12 μm, but positively correlated with the volume of particles >80 μm. The results suggested that the greater percentage of larger GMP particles is, the more GMP content there is in wheat grain. Size distribution of glutenin macropolymer (GMP) particles significantly affects the quality of final products in wheat. Six wheat varieties in eastern China were used for investigating the GMP content, particle size distribution and their relation. The results showed that the particle diameter of GMP changed from 0.38 μm to 269 μm. A typical bimodal curve of volume distribution of particles with peak values ​​ranged from 4.44 μm to 5.36 μm and from 45.76 μm to 116.30 μm, respectively. Number distribution of particles showed the typical population with peak values ​​in the range of 0.57-1.00 μm. Proportions of granules <12 μm, 12-80 μm and> 80 μm were in the range of 17.1% -47.8%, 32.1% -50.3% and 10.2% -38.1% of total volume, respectively. content of GMP was negatively correlated with the volume of GMP particles <12 μm, but positively correlated with the volume of particles> 80 μm. The results suggested that the greater percentage of GMP particles is, the more GMP conte nt there is in wheat grain