Abstract: Through the experiment of two types of two double-span, single-story unbonded prestressed concrete frames under horizontal low cyclic loading, their destructive formation, ductility feature, strength, stiffness and energy-dissipating capacity were investigated. In the first type, beams and columns were collocated with unbonded prestressed bars, and in the second type, only beams with unbonded prestressed bars. The experimental result shows that non-prestressed frame members dissipate a amount of energy and columns have greater energy-dissipating capacity than beams, and that when the beams and columns of a frame are collocated with unbonded prestressed bars most of energy will be concentrated in its central column.