Recently, low interfacial toughness (LIT) materials have been developed to solve large-scale deicing problems. According to the theory of interfacial fracture, ice detachment is dominated by strength-controlled or toughness-controlled regimes, which are characterized by adhesive strength or constant shear force. Here, a new strategy is introduced to regulate the interfacial toughness of poly(dimethylsiloxane) (PDMS) coatings using silicon dioxide nanoparticles (SiO2 NPs) and phenylmethyl silicone oil (PMSO). By systematically adjusting the doping proportion of SiO2 NPs and PMSO, it is found that a lower interfacial toughness can be achieved with a lower constant shear force. The synergistic effect of the two dopants on the adhesive strength and interfacial toughness is analyzed. Meanwhile, finite element method (FEM) analysis of ice detachment is conducted to show the cracking process intuitively and explicate the mechanism of lowering the interfacial toughness of PDMS by doping SiO2 NPs and PMSO. It can be concluded that the cohesive zone material (CZM) model is effective for simulating the deicing process of PDMS coatings and provides a comprehensive understanding of the modulation of interfacial toughness.