The nozzle clogging in vacuum induced melting gas atomization (VIGA) process was investigated. To understand the influence of tip shape of the delivery-tube on nozzle clogging more accurately, the interface tracking method of computational simulation fluid volume was adopted to simulate the two-phase flow in the primary atomization region. Results show that the small platform at the end of the draft tube is the key factor leading to the nozzle clogging. Therefore, the expansion angle (30°, 35°, 40°, 45°) of the delivery-tube is improved to shorten the width of the small platform. Thus, the nozzle clogging is solved, the atomization continuity is realized, and the atomization efficiency is improved. Additionally, when the expansion angle is 40°~45°, the powder has better morphology with the particle size of 21~25 μm. The numerical simulation results under different modification aspects display similar trends to the experiment ones. This research is of guidance significance and reference value to understand the nozzle clogging process of VIGA process.