The invention provides a preparation method of a 
yeast cell extracting solution, the 
yeast cell extracting solution and a method for synthesizing 
protein in an 
in vitro system by virtue of the 
yeast cell extracting solution, as well as a kit containing the yeast cell extracting solution. The kit, which is more convenient than a conventional method, is applicable to 
protein synthesis in the 
in vitro system; transformation, culture and crushing can be prevented; a great amount of using time and cost can be saved; various types of proteins can be expressed, and influence of 
protein toxicity can be prevented; and a plurality of protein complexes can be expressed, without the use of a high temperature at 37 DEG C. In addition, as a 
raw material adopted by the invention, yeast cell is simple to cultivate, convenient to operate, rapid to propagate and relatively low in cost; a prepared 
yeast extract has a capacity of modifying translated protein, the 
yeast extract is suitable for large-scale preparation and has an 
advantage of industrial production; and the 
yeast cell extract, which is prepared into freeze-dried 
powder by virtue of a vacuum freeze-
drying method and is preserved at low temperature or high temperature, is convenient to transport.