The invention discloses a high-purity 
nickel-based high-temperature 
alloy and a preparation method of spherical 
powder of the high-purity 
nickel-based high-temperature 
alloy. The 
alloy comprises the following steps of selecting high-purity 
metal ingredients, 
smelting in a vacuum induction suspension 
smelting furnace, realizing pure 
smelting by controlling parameters such as smelting vacuum degree, refining temperature, time and the like, then pouring to obtain a steel 
ingot, and preparing the steel 
ingot into a bar; carrying out smelting, atomizing and powdering on the bar through EIGA and PREP technologies to obtain spherical 
metal powder; adopting vibrating screening and 
airflow classification, and classifying spherical 
powder under the protection of 
inert gas. According to the method, the content of 
nonmetal impurities is effectively controlled through 
raw material smelting control, atomization 
process control and post-treatment control, so that chemical elements of the powder have extremely high purity, and the high-purity high-temperature alloy spherical powder is not prone to generating cracks and other defects in the subsequent 
laser additive printing and 
laser cladding process and is good in 
binding force, high in strength, good in 
toughness and good in 
mechanical property, and the powder can be used for repairing high-end parts.