Intensification of knowledge of tax volunteers will have a positive impact in providing assistance to taxpayers, then taxpayers do not hesitate to be accompanied in reporting their tax obligations because taxpayers do not need to conduct tax consultations with the Tax Office ( KPP or KP2KP) so that for the mission of binding the level of awareness and compliance of taxpayers. Therefore, efforts are needed on how to make the function of Tax Volunteers maximize their role. This study aims to examine the effect of training instructors, training methods, training m−aterials and training time on the knowledge intensification of Tax Volunteers. This study uses a quantitative approach with a sample of 132 Tax Volunteers from the Central Java DGT Office 2. The type of data used is primary data obtained by distributing questionnaires. The data analysis technique used multiple linear regression analysis. The results of this study indicate that the variables of training instructors, training methods and materials have no effect on the knowledge intensification of tax volunteers, but the time has a significant effect on the knowledge intensification of tax volunteers.