Poly(vinylidene fluoride) is a pivotal piezoelectric polymeric building block for advanced electronics, whose piezoelectric properties are determined by the proportion of the polar β phase, while the α phase is generally the predominant phase of PVDF. Thus, it is of great importance to transform more of the α phase to the β phase in PVDF for the device applications. Molecular Dynamics simulations are computational methods to study the physical movements of atoms and molecules. The cornerstone of Molecular Dynamics simulations is Newton’s second law: F=-ΔE=ma. Based on molecular dynamics simulations, this work assessed the phase transition behaviors of PVDF from α phase to β phase under a coupled electric-strain field. It is found that the presence of strain can significantly reduce the threshold strength of the electric field that triggers robust and stable phase transitions. Similarly, the presence of electric field will reduce the required stress or strain that initiates phase transitions. Quantitative analysis of phase proportions change during transition Process is presented, and two different pathways of phase transition are identified under pure electric field and coupled electric-strain field, respectively. Phase transitions of semi-crystalline α phase and β phase models are also investigated to broaden our research to more practical scenarios. The findings obtained in this work could provide helpful guidelines for manipulating PVDF with required piezoelectric properties. These findings are anticipated to provide useful references and guidance for designing and manufacturing high-sensitivity piezoelectric polymer sensors and generators, crucial for applications in clean energy and advanced electronics.