The main difference between Tezpur University and Gauhati University is that the former is a central university while the latter is a state university. So, TU has a residential campus, central funds, and better infrastructure compared to Gauhati University. 

In terms of quality of education, there is no such difference between the two universities. GU being the older university has better experiences. However, TU has improved a lot over the years. Both universities are well recognized in India.