We study sonic horizon formation dynamics for Bose-Einstein condensate systems with higher-order nonlinear interaction. Based on the Gross-Pitaevskii equation incorporating higher-order nonlinear effects and through a variational method, we derived the criteria formula for sonic horizon occurrence. The key features of the sonic horizon are pictorially demonstrated, and we identified the stabilization and widening metastable effects of the higher-order nonlinear interaction, from which the quantitative results can be used to guide relevant experimental observations of sonic black holes with higher-order nonlinear effects.