a bed unit including a bed body and a plurality of anchoring components connected to a periphery of said bed body; and

a foldable frame unit operable to move between an unfolded state and a folded state, and including first and second frame sections that cooperate to define a bedding space, that are coupled movably to each other, that have said anchoring components of said bed unit coupled thereto, and that include first and second end parts, respectively;

wherein said bed body of said bed unit is stretched tensely over said bedding space when said foldable frame unit is in the unfolded state;

wherein said first end part of said first frame section has a coupling edge indented to form a coupling notch that opens in a direction away from said bed body, and a guiding edge extending from said coupling edge and indented to form a securing notch that opens toward said second end part of said second frame section when said foldable frame unit is in the unfolded state;

wherein said second end part of said second frame section is provided with a coupling shaft to be received movably in said coupling notch in said coupling edge of said first end part of said first frame section, and a securing shaft to be received in said securing notch in said guiding edge of said first end part of said first frame section;

wherein, when said coupling shaft is extended into said coupling notch, and said foldable frame unit is operated to move from the folded state to the unfolded state, said securing shaft is guided along said guiding edge of said first end part of said first frame section and is subsequently received in said securing notch such that said coupling shaft and said securing shaft cooperate with said first end part of said first frame section to secure said foldable frame unit in the unfolded state;

wherein said second end part of said second frame section is tubular and is formed with an aligned pair of securing openings and two radial nicks in spatial communication with said securing openings, respectively;

wherein said securing shaft includes a shaft body and a plurality of radial securing protrusions mounted on said shaft body, said shaft body being operable to extend through said second end part of said second frame section via said securing openings such that said securing protrusions are extended into said second end part of said second frame section via said nicks; and

wherein said securing protrusions prevent said shaft body from moving out of said second end part of said second frame section when said securing protrusions are misaligned with said nicks.