Abstract: A tilting angle-adjustable bicycle saddle includes a mounting frame, which is adapted to be affixed to a seat post of a bicycle, having a holder base provided with a smoothly arched bottom wall, an inner shell having a chamber for pivotally accommodating the holder base therein, and two screw bolts. The chamber of the inner shell has two opposite sidewalls pivotally connected to the holder base of the mounting frame at two sides, a smoothly arched bottom wall fitting over the bottom side of the smoothly arched bottom wall of the holder base, a bottom center opening, and two bottom through holes. And, the two screw bolts are respectively inserted through the bottom through holes of the inner shell and respectively screwed up with the holder base of the mounting frame to lock the inner shell in position.