Objective: to search for conceptual issues, features and prospects of development of tax law principles and tax obligation institute in the context of modern digitalization trends.Methods: the study is based on a set of general legal (analysis and synthesis, induction and deduction) and special-legal (formal-legal, comparativelegal) methods of cognition.Results: the main features of tax law principles characterizing their digital development were defined, namely: the expansion of the list of such principles and the changes in their content, predominantly at the level of institutional principles of taxation. A conclusion is made that in the digital era the tax law principles retain their theoretical significance as the most important category of the relevant science. The author states that the digital transformation of the institutional principle of tax fulfillment independence takes place mainly in the following directions: firstly, the range of taxpayers is expanded, in respect of which the duty to calculate tax can be imposed on a tax authority; secondly, the mechanism of the tax obligation execution is changed, among other things, by increasing the tax obligations of state authorities and credit organizations.Scientific novelty: the paper assesses the approaches used in the scientific literature and normative-legal framework related to transformation of the taxation principles due to the intensive use of information and communication technologies in tax relations. The author also analyzed the digital transformation of the principles of tax obligation as one of the main tax-legal institutions.Practical significance: is due to the lagging pace of tax legislation development in the Russian Federation compared to the objective processes of creation and application of new information and communication technologies in tax relations and adjacent spheres. The main provisions and conclusions of the study can be used as a basis to improve the tax legislation, as they develop knowledge about new tax law institutions – professional income tax, tax monitoring, single tax payment, and automated simplified taxation system.