The invention discloses a nickel-base high-temperature alloy GH4720Li smelting technique. The technique comprises the following step: carrying out smelting by a triple (VIM+VAR+VAR) smelting technique according to the composition requirements for the GH4720Li alloy (No.1 or No.2 Ni, vacuum-degassed Cr, sponge Ti, Al beans, metal Co, NiW alloy, NiMo alloy, carbon, NiMg alloy, NiB alloy and zirconium sponge), thereby obtaining the GH4720Li high-temperature alloy cast ingot. The novel triple smelting technique enhances the metallurgical quality of the GH4720Li alloy; especially the gamma' phase forming elements Al and Ti for performing the main reinforcement function in the GH4720Li alloy have high composition control precision and favorable uniformity; and the other alloy elements have the advantages of less segregation and high composition control precision. The obtained alloy has impurity element content, and the properties have long-term stability at 650-750 DEG C.