In this study, we investigated the single-path and multipath conversions of ultracold bosonic heteronuclear tetra-atomic molecules using the generalized stimulated Raman adiabatic passage technique. First, we established a mean-field model and obtained the corresponding dark state solutions and two-photon resonance conditions. Next, we compared the molecule conversion dynamics of the single-path and multipath cases and found that constructive interference effects existed in the multipath cases; this could increase the molecular conversion rate. In particular, for the three-path scheme, the interference effect was obvious and the conversion rate was high. We further studied the influence of external field parameters on the conversion rate of the multipath scheme by varying the pulse intensity and found that the influence had two sides: constructive and destructive interference, respectively, which increased and decreased the conversion rate of molecules.