Abstract:Very clear electrophoresis patterns have been gotten by isoelectric focusing (IEF) and microoper-ation of single pollen grains (d≈150um) from Cucurbita moschata . The results showed that there were different protein bands among pollen grains from one flower. This segregation occurred with a classical 1: 1 Mendelian ratio by statistics in all experiments. The technique of IEF of single pollen grains and micro-oper-ation provides a new and quick screening test applied to plant genetic breeding and developmental research.