The mixing of scalar mesons is an open problem. In this work, the idea of the mixing of scalar mesons will be applied to dibaryon system on quark level. By introducing the mixing of scalar mesons, we dynamically investigate the structure of possible nonstrange dibaryons in the chiral S U(3) quark model by solving the resonating group method equation. The results show that no matter what kind of mixing is considered, the binding energies of nonstrange dibaryons would become stable if reasonable parameters are used.