This research work presents an innovative tensorial analysis of network (TAN) model of asymmetrical 1:2 Y-tree interconnects. The modelling methodology is built with Kron–Branin formalism. The analytical Z -matrix equivalent to the assumed multi-port system is fundamentally established from the transmission line Kron–Branin topology. Then, the equivalent S-parameters of the two-level Y-tree system are established. The developed model is validated with S-parameter simulations of microstrip Y-tree interconnects structure from DC to 8 GHz.