National Open University and Guangdong Open University are both adult higher education institutions in China, but there are some differences between them:

1. Independence: National Open University is an institution of higher learning directly under the central government, and Guangdong Open University is a local institution of higher learning under the Guangdong Provincial Department of Education.

2. Degree conferring: The Open University of China has the right to confer degrees, and can award bachelor's, master's and doctoral degrees; At present, Guangdong Open University only has the right to award bachelor's degrees.

3. Curriculum: The curriculum of the two schools is slightly different. The curriculum of National Open University is broader and deeper, involving many fields, while Guangdong Open University pays more attention to cultivating applied talents and practical courses.

4. Examination methods: The examination methods of National Open University include open-book examination and closed-book examination, while that of Guangdong Open University is mainly closed-book.

Generally speaking, the National Open University is a more comprehensive and systematic learning institution with higher popularity and academic recognition, while Guangdong Open University pays more attention to practicality and employment orientation, which is more suitable for professionals and students with certain practical experience.