Global navigation satellite system (GNSS) has became one of the major technologies of earth ionospheric exploration because of its advantages of 24 hours observation, easy deployment and high precision. Five ionosphere analysis centers are established in the International GNSS Service (IGS) Organization to provide global ionospheric grid models,i.e. European Orbital Determination Center (CODE), Jet Propulsion Laboratory (JPL) , University of Politecnica Catalunya (UPC), European Space Agency (ESA), and Chinese Academy of Sciences (CAS). The ionospheric correction model based on GNSS has been far-reaching employed in deep space exploration, positioning, navigation and communication engineering, such as China's lunar exploration project. Since 2007, China's lunar exploration project has accomplished Chang’E (CE)-1\CE-2\CE-3 missions, and the current CE-4 lunar exploration mission is the first international exploration of the back of the moon. Very Long Baseline Interferometry (VLBI) technology is applied on orbit determination of China’s lunar exploration Chang’E-4. While, the ionosphere becomes the largest error source for S band observations. In such case, SHAO (Shanghai Astronomy Observatory)-TEC model is established to decrease the impactof ionosphere, which is composed of spherical harmonic coefficients (15*15 order). The model can ensure the timeliness of data work. More GNSS stations around the VLBI stations are utilized to improve the precision. Compared with CODE (European Orbital Determination Center) -TEC model, the precision of orbit determination residual based on SHAO- TEC model raises about 2ns.