The invention discloses a full-load precise 
ammonia spraying 
system with functions of online speed field leveling and concentration field measuring. The full-load precise 
ammonia spraying 
system comprises a zone 
flue gas speed measuring device and a zone 
NOx (oxynitride) concentration measuring device corresponding to a vertical 
flue zone between a first corner fixed flow guide plate and a primaryammonia spraying grid, and a secondary micro-
ammonia spraying and supplementing 
system, a zone speed measuring device, and a zone ammonia and 
nitrogen integrated concentration measuring device whichare arranged from top to bottom corresponding to each zone between a flow 
equalizer and a catalyst layer; a zone ammonia and 
nitrogen integrated concentration measuring device is arranged corresponding to each zone between the catalyst layer and an exit 
flue; a zone 
flue gas speed measuring device, a zone 
NOx concentration measuring device, a zone speed measuring device and the zone ammonia and 
nitrogen integrated concentration measuring device are used for respectively transmitting the measuring data to an input port of a 
control unit, and the 
control unit is used for generating a control adjusting 
signal, and sending to a primary ammonia spraying grid, a dynamic flow field leveling flow guide device, and a secondary micro-ammonia spraying and supplementing system via an output end. The full-load precise ammonia spraying system has the advantages that the speed field in front of the catalyst can be flexibly leveled according to the characteristics of the 
flue gas flow field formed bythe combination of different 
coal types, different loads and different combustors.