Pickup truck tonneau cover

A pickup truck tonneau cover, comprising:

• one or a plurality of cover plates;
• and
• a pair of folding apparatuses respectively mounted at two side walls of a pickup truck bed, wherein,
• each folding apparatus comprises a mounting frame and a folding mechanism;
• the mounting frame is mounted at an inner side of the truck bed;
• the folding mechanism is provided within the mounting frame;
• a plurality of mounting arms are provided at the folding mechanism;
• one end of the cover plate is mounted at a corresponding mounting arm of one folding mechanism, and another end of the same cover plate is mounted at a corresponding mounting arm of another folding mechanism;
• and
• the folding mechanism is configured to telescopically move in a length direction of the truck bed, such that the folding mechanism is switchable between an unfolded state and a folded state, and the mounting arms move along with the folding mechanism, such that the cover plate is switchable between a horizontal state and a non-horizontal state.