This paper presents the application of the General Data Protection Regulation (hereinafter GDPR) in the electronic business of financial institutions. The introduction of GDPR has set new standards and conditions for the use of personal data, especially in the case of individuals. Due to its specific scope, the financial sector uses personal data as an integral part of the regular processing of documentation and reporting. It is for this reason that the financial sector is often faced with the problem of full implementation of GDPR. Electronic business, on the other hand, makes personal information even more accessible and susceptible to manipulation. In this context, the marketing communications of financial institutions, as well as financial reporting in a bookkeeping business that requires the processing of personal data in the context of satisfying the accuracy of financial reporting, may be best considered. Analyzing all of the stated challenges of implementing GDPR at the end of the paper, it was determined that the electronic business of the financial sector must adapt to all requirements of personal data protection in order to avoid unwanted data manipulation.