HFO1234ze(E) is an environmentally friendly SF6 substitute gas with prominent application potential. To suppress the generation of the HFO1234ze(E) solid decomposition products, which may cause great hazards to the gas-solid insulation strength, a gas mixing scheme screening method based on the reactive force field (ReaxFF) molecular dynamics (MD) simulation was innovatively proposed. The simulation results show that the inhibitory effect of O2 on the formation of HFO1234ze(E) solid products is better than those of CO2 and CF4. Further study shows that when O2 accounts for 3.33% of the gas mixture, the solid precipitate content is reduced by 48%. The experimental study shows that an O2 content of 3.33% can inhibit the generation of solid products by more than 50%. Besides, compared with HFO1234ze(E)-N2, the DC breakdown voltage of HFO1234ze(E)-N2-O2 is slightly increased, and the breakdown voltage dispersion degree and continuous breakdown voltage drop rate are decreased. This work gives a feasible solution for the suppression of HFO1234ze(E) solid decomposition products and provides an efficient method for solving similar problems of environmentally friendly insulating gas in C/F/O/N systems.