Fat mimics are one of the most common substitutes for animal fats in processed foods. However, basing on high internal phase Pickering emulsion (HIPPEs) gel imitate adipose tissue to achieve the desired strength and elastic, while the formation and stabilization mechanism are barely understood. Here, we proposed a strategy to fabricate rigid-flexible double network using κ-carrageenan (CA) and bacterial cellulose (BC), in oder to improve the mechanical performance of HIPPEs gel. The effects of different ratios of CA/BC (2:1, 4:1, 8:1) and K+ addition on the properties of HIPPEs-CA/BC gels were investigated. Results showed that HIPPEs-CA/BC 8:1 & K+ exhibited better rheological, textural, oil holding capacity and organoleptic properties. Thermal softening behavior of HIPPEs-CA/BC 8:1 & K+ was similar to the pork adipose tissue. The microstructure of gel demonstrated that HIPPEs-CA/BC 8:1 & K+ was featured with honeycomb-like pore and network walls, which in turn comprise interpenetrated double network structures. Meanwhile, it showed an ultrahigh stress, high Young's modulus and good cyclic compress behavior. Additionally, the hydrogen bonds and K+-cross-linked were proved to play crucial roles in facilitating the formation of a stable and elastic CA/BC matrix. This study establishes structure-performance mechanisms in strongly and elastically structured HIPPEs gels, providing an advanced strategy for developing HIPPEs gel with promising applications in adipose tissue substitutes.