Magnetic properties of amorphous Gd-Co ferrimagnetic films prepared by magnetron sputtering have been studied for various thicknesses. In a certain temperature range close to the magnetic compensation temperature, triple hysteresis loops and the characteristic features of the tempera-ture dependencies of magnetization were observed for all samples under consideration. Two-layer film model with an inhomogeneous chemical composition and a spin-flop transition scenario in two sub-lattice ferrimagnet was employed for understanding the origins of these phenomena. Within the framework of the spin-flop transition, the inter sub-lattice exchange coupling constant was estimated using various methods.