Delonix regia Raf. (DR) and Gleditsia triacanthos L. (GT) are deciduous trees of the Fabaceae family. Different parts of the two plant species were used in folk medicine for the treatment of various ailments. This study aims to prepare cold (CPS) and hot (HPS) from the Fabaceae fruits of DR and GT for the first time, in addition to chemical and biological investigations. CPS and HPS were isolated, filtered, concentrated, and ethanol precipitated. Quantitative analyses of the two fruit extracts, including their total ash, sugar, protein, and phenolic content, were conducted. Chemically, they were elucidated by gas liquid chromatography (GLC) and Fourier-transform infrared spectroscopy (FTIR). The FTIR and GLC analyses showed that both CPS and HPS have galactomannan-type polysaccharides. Biologically, in vitro anticancer activity against four human tumor cell lines, in vivo hepatoprotective activity against CCl4-induced liver injury, and in vivo antioxidant activity were studied. The CPS and HPS of the two fruits studied showed very strong selective in vitro cytotoxic activity against four human tumor cell lines and very weak activity against normal human lung fibroblasts. They also have significant curative activity for the injured liver and have potent in vivo antioxidant activity.