A biaxial pivoting mechanism includes a supporter disposed on a first module, a base connected to the supporter, a rotating component disposed between the supporter and the base. A track is formed on a lateral wall inside the base. The rotating component includes a shaft portion pivoting to the supporter, and a sheathing portion connected to the shaft portion. A hole is formed on the sheathing portion. The sheathing portion pivots to the supporter via the shaft portion for accommodating inside the accommodating space. The biaxial pivoting mechanism further includes a sleeve movably disposed inside the hole. The sleeve includes a protruding portion. The sleeve is rotated relative to the rotating portion by sliding the protruding portion along the track. The biaxial pivoting mechanism further includes a holder disposed on the sleeve for holding a second module.