Abstract: A body exerciser includes two leg-supporting members having first proximate ends pivoted to a seat member, and first distal ends swingable relative to the seat member on a horizontal plane. A guiding member has a second proximate end secured to the seat member between the first proximate ends, and a second distal end. A sliding member is mounted slidably on the guiding member, and is connected pivotally to the first distal ends of the leg supporting rods by two connecting members, respectively. When the user sits on the seat member and bends forward to move the sliding member toward the second distal end, the connecting members will cooperate to spread apart the leg supporting members for spreading apart the user's legs so as to exercise the user's trunk and legs.