The rising frequency and severity of abnormally high temperatures pose significant threats to the health and productivity of exposed workers. This paper identifies a labor channel of corporate exposure to climate risk, measured using firms’ reliance on workers exposed to high temperatures while performing job duties. Consistent with the physical risk mechanism, unexpected extreme heat significantly reduces firm-level and plant-level labor productivity, making labor less efficient than capital as a production input. Firms adapt to these disruptions by shifting toward more capital-intensive production functions, i.e., higher capital-labor ratios. Firms further respond by investing more in robotics-related human capital and developing more automation-related technology. At the macro level, climate change impedes the growth of high-exposure industries in hot areas. My findings highlight that climate change accelerates automation in occupations and firms exposed to rising temperatures.