These datasets were generated for the master thesis with the title "Altmetrics and its use in the evaluation of scientific research" (in Czech "Altmetrie a její využití při hodnocení vědeckého výzkumu"), that was submitted in 2022 at the Institute Information Studies and Librarianship, Charles University, Prague, Czech Republic. There are 3 files, where the first one "Příloha_číslo_1-processed_data.xlsx" contains processed and analyzed data from the other two. "Příloha_číslo_2-data_altmetrics_Kvet_1st_download.csv" is the file with raw altmetric data downloaded on the 9/1/2022. "Příloha_číslo_3-data_altmetrics_Kvet_2st_download.csv" are the same data but downloaded two months later to see the difference. Altmetric data came from PlumX and Altmetric.com aggregators. Before publishing them here there were completely anonymized so there is no possibility to assign them to particular research papers. Dataset contains altmetric data of the research documents published in the period from 2017 to 2021. All documents have affiliation to the Czech Republic. The tool for collection and analyzation is available on Github here: https://github.com/kvetjo/Altmetrics_analyze_tool Thesis reference in Czech: KVĚT, Jonáš. Altmetrie a její využití při hodnocení vědeckého výzkumu [online]. Praha, 2022 [cit. 2022-05-03]. Diplomová práce. Univerzita Karlova. Filozofická fakulta. Ústav informačních studií a knihovnictví. Vedoucí práce Jan Dvořák.