Small-angle neutron scattering has been applied to investigate in detail the structural relaxation of bulk amorphous Cu12.5Ni10Zr41Ti14Be22.5 alloy in the supercooled liquid range (620-673 K) and its effect on subsequent crystallization around the crystallization point (673 K), The interference events from typical phase separation were recorded as the alloy was annealed in the supercooled liquid range, It was revealed that the crystallization in the alloy which was previously relaxed in the supercooled liquid range was significantly prohibited, and further phase separation was observed. Considerable temperature dependence of these phase separations was observed, It has been demonstrated that the phase separation developed via the spinodal mode and the achieved microstructure consisted of one droplet-like supercooled liquid phase embedded in the similarly disordered matrix, The droplets showed a bar-like pattern and distributed in a relatively regular form in the matrix. The phase separations exhibited sluggish coarsening kinetics with much smaller exponent than the Lifshitz-Slyozov-Wagner value. However, the dynamic scaling property of the phase separations at different temperatures has been approved by our scaling analysis.