Recent efforts to detect and manipulate Majorana fermions in solid state devices have employed topological insulator (TI) nanowires proximity coupled to superconducting leads (SC). We studied the transverse magnetoresistance of Bi2Te3 and Bi0.83Sb0.17 TI microwires contacted with superconducting In2Bi leads [1]. The equidistant in transverse magnetic field (up to 1 T) magnetoresistance (MR) oscillations at the TI/SC interface have been observed at various temperatures (4.2 – 1.5 K) both in Bi2Te3 and in Bi0.83Sb0.17 samples. The oscillations almost disappear when the measurement temperature reaches the superconducting transition temperature in In2Bi. The amplitude of the MR oscillations also decreases with increasing magnetic field; in magnetic fields of B > 0.6 T at T = 1.5 K, oscillations are not visible. Possibly, the observed oscillations can be the Aharonov-Bohm oscillations of the magnetic flux quantization. In this case, a closed trajectory is formed at the edge states of the TI/SC interface. The oscillation period ΔB=(h/e)/S were h/e is flux quantum, S is the cross-sections area of closed trajectory; then, taking into account the oscillation periods, for Bi2Te3 microwire the effective trajectory diameter should about 500 nm, while for Bi0.83Sb0.17 microwire – about 300 nm. In both cases, these diameters are much smaller than the corresponding microwire diameters. Different assumptions about the nature of the observed effect are discussed.