The invention provides a method and packaging structure for detecting the water and 
oxygen penetration rate of a back plate. The method includes the following steps that a 
metal electrode pattern is formed in the back plate to be detected; a 
calcium film is formed on the back plate provided with the 
metal electrode pattern; the back plate provided with the 
metal electrode pattern and the 
calcium film is used as a partition plate to separate a 
drying chamber from a moist chamber; the change value of the electrical 
conductivity of the 
calcium film is measured through the metal electrode pattern, and the water and 
oxygen penetration rate of the back plate is determined according to the measured change value. According to the method and packaging structure for detecting the water and 
oxygen penetration rate of the back plate, the calcium film is arranged on the back plate to be detected, the whole back plate is used as the partition plate separating the 
drying chamber from the moist chamber, and the water and 
oxygen penetration rate is detected; compared with the mode that only back plate packaging materials are detected in the prior art, the method and packaging structure for detecting the water and 
oxygen penetration rate of the back plate have the advantages that the real environment of a device needing to be protected can be reflected more really, and detection accuracy of the water and 
oxygen penetration rate of the back plate is improved. Moreover, an electrode used for detecting the electrical 
conductivity is made on the back plate to be detected so that detection difficulty can be lowered.