Herein, we investigate a scheme to generate continuous double-mode squeezed vacuum states based on a beam splitter by assuming that a beam splitter can cause entanglement, and the entangled conditions are solved. For a 50∶50 beam splitter, the phase shift influencing factor is analyzed and extracted. The relationship between the relative squeezing angle of quantum state output and input and the phase shift influencing factor is analyzed based on the quantum state conversion and the Wigner function. Subsequently, the Duan criterion is used to determine whether the output is entangled, and logarithmic negativity is defined for measuring the degree of entanglement. The results indicate the presence of a periodic effect in the entanglement characteristics of the outputs is due to the beam-splitter phase shift influencing factor and the relative squeezing angle provided as input; in a half-single pass, outputs are the processes associated with unrelated properties, partially entangled properties, and maximally entangled properties. Increasing the degree of squeezing provided as the input will cause an increase in output when the maximally entangled states are obtained as outputs. This study provides some concepts for using single-mode squeezed vacuum states to produce the maximally entangled states.