The main purpose of the article is to analyze the problems and factors determining the quality and structural perfection of protein crystal. Special attention is paid to crystallization processes by means of temperature. We consider the equipment and methods of protein crystallization employed in our country and abroad. The findings of this research led to developing a method of controlled protein crystallization, which allows real-time division of nucleation and crystal growth processes. This method does not require large amounts of protein solutions and excludes the possibility of crystal damage during diffraction studies. The construction of such apparatus implements a modular principle: better throughput is achieved by aggregation of single-type blocks. Their basic design allows modernizing and upgrading for increasing the number of growth cells and using diagnostic and test equipment.