The invention discloses an automatic 
water quality detection device. The automatic 
water quality detection device comprises a quantitative sampling pump, a 
water sample detection tank, a 
sample chamber, a detection chamber, a quantitative liquid feeding device, a microscale continuous liquid feeding device, a micro-flow meter, a treatment module, a power supply module and a controller. The 
water sample detection tank is fixed in the 
sample chamber, one side of the 
sample chamber is provided with a light emitting chamber and the 
water sample detection tank is connected to the quantitative sampling pump through a 
pipe. The automatic 
water quality detection device can eliminate the analysis error between different analysts, improve the analysis efficiency, realize fast detection and early warning of key detection indexes such as 
calcium hardness and total 
alkalinity of the circulating cooling water 
system, remind to reasonably control the concentration multiple during the circulating water 
system operation, prevent unnecessary 
discharge of pollutants and save 
water resources. The device can effectively guide the stable feeding of a 
water treatment agent and prevent fluctuation of theconcentration of the 
water treatment agent. The device realizes 
continuous analysis, the 
operating environment is safe, the data is reliable, the error is small, and the 
analysis data can also be transmitted in real time.