This book constitutes the proceedings of the 26th European Conference on Advances in Databases and Information Systems, ADBIS 2022, held in Turin, Italy, in September 2022. The 23 full papers presented together with 5 keynote and tutorial papers were carefully reviewed and selected from 90 submissions. The papers are organized in the following topical sections: ​keynote talk and tutorials; graph processing; time series and data streams; on line analytical processing; advanced querying; performance; machine learning; data science methods.