We developed an anthropomorphic talking robot, Waseda Talker No. 6 (WT-6), which generates speech sounds by mechanically simulating articulatory motions and aero-acoustic phenomena. WT-6 possesses 17 degrees of freedom (DOF): a 5-DOF tongue, 1-DOF jaws, 4-DOF lips, a nasal cavity, and a 1-DOF soft palate as articulators; and 5-DOF vocal cords and 1-DOF lungs as vocal organs. The vocal cords, tongue, and lips are made from the thermoplastic rubber Septon, whose elasticity is similar to that of human tissue. WT-6 has three-dimensional (3D) lips, tongue, jaw, and velum, which form the vocal tract structure. It also has an independent jaw opening/closing mechanism. The previous robot in the series had a two-dimensional tongue and could not produce human-like tongue shape. The new tongue can form 3D shapes, and thus, is able to produce more realistic vocal tract shapes. The vocal cord model consists of two folds, and is constructed with a structure similar to the biomechanical structure of human vocal cords. These vocal cords can vibrate in complex phases, similar to those of a human. With these mechanisms, the robot can reproduce human speech in a more biomechanical manner, and thus, can produce a voice closer to that of a human.