The invention provides a 
protein immunogold labeling method for a cryoelectron 
microscope. The 
protein immunogold labeling method comprises the following steps of (1) respectively pretreating a grid of the frozen 
electron microscope by utilizing a poly-L-
lysine solution and PBS (
Phosphate Buffer Solution); (2) putting the grid in a culture dish with the front surface facing upwards, dripping a sample onto the grid, standing, incubating, and eluting with PBS (
Phosphate Buffer Solution); 3) adding a sealing agent into the culture dish, standing, incubating, and eluting with PBS; 4) adding a primary 
antibody, namely a 
specific antibody of the 
target protein, into the culture dish, standing, incubating, and eluting with PBS; 5) adding a secondary 
antibody, namely an immune gold 
antibody selected according to the species of the primary antibody, into the culture dish, standing, incubating, and eluting with PBS; and 6) taking out the grid, imaging by using a freezing 
electron microscope, andanalyzing image data to obtain a 
target protein structure. The method is advantaged in that an immunolabelled 
protein technology and a freezing 
electron microscope 
tomography technology are combined,so the 
target protein is observed in the freezing 
electron microscope imaging, and the structure is analyzed at the same time.