A pesticide droplet leaf transmembrane absorption observation apparatus: an outer anti-mist glass cover (13) is shrouded over a lower base plate (14) to form an outer anti-mist chamber, used for accommodating a whole plant, a support frame (12) being arranged inside an outer atomising chamber, an inner anti-mist glass cover (9) being shrouded over an upper top plate of the support frame (12) to form an observation chamber, an outer atomising nozzle (6) and an inner atomising nozzle (8) respectively being inserted into the outer anti-mist chamber and the observation chamber, a temperature controller (2) respectively being connected to the outer atomising nozzle (6) and the inner atomising nozzle (8); a temperature sensor (7) is arranged inside the observation chamber and is connected to a data collection computer (1), a leaf pressing mechanism (10) being arranged inside the observation chamber and being used for pressing the leaves of the plant; a first digital camera (3) and a first microscope (4) and a secon