As the aggravation of the greenhouse effect, global warming has become a serious change for the modern animal husbandry and caused billions of dollars of losses annually around the world. Elevated temperature has become the major abiotic stress affecting animal growth. During heat shock, organisms experience orchestration of a multitude of biochemical and physiological changes to acquire heat resistance, and most of these depend on changes of heat shock proteins (Hsps). Therefore, this paper aimed to state the mechanism of the heat shock signal transduction that the Ca~(2 +)- CaM involved in. The concentration of intracellular free Ca~(2 +) is increased by heat stress, and CaM is activated by the increased Ca~(2 +) , then CaM function on the 2 downstream target proteins that effect the transcriptional activity of HSF1 to regulate the expression of Hsp70. There are 2 specific pathways participating in the expression of Hsps: ① The transcriptional activity of HSF1 is increased by the phosphorylation of HSF1 (Ser230), which was activated by CaMKⅡ that one of the downstream target proteins regulated by Ca~(2+)-CaM; ② During heat shock, HSF1 is released, and activated by the compound of Hsp70- CaM for that Hsp70 is another downstream target proteins regulated by Ca~(2+)-CaM, HSF1 is converted from a transcriptional inactive monomer to active trimmer that is capable of binding to HSE and exhibits transcriptional activity, and finally induced the expression of Hsp70. The regulation activity of the HSF1 is the central mechanism of transcriptional regulation for Hsps gene expression. This paper reviewed the mechanism of the Ca~(2 +)- CaM- HSF1- Hsp70 signal transduction system in reception, transduction and response to heat stress.