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Dendroclimatic records in areas with high relative humidity and low thermal amplitude are manifestly scarcer and only a few studies are applied to species that are present in areas with weak seasonality. The Azores archipelago with temperate climate, with low thermal amplitude, has unique biodiversity, including the Azorean holly, Ilex azorica Gand., that is dominant in most extant natural forests. Hence, the importance of understanding its behavior and relation with climate. In this study, we try to understand tree-ring patterns of this species and examine the relationship between radial tree growth and main climatic drivers. For this purpose, we sampled four populations from São Miguel Island and two from Terceira Island. We found a diffuse-ring porous wood with a common layer of vessels associated to the ring boundary, which was critical to identify annual tree-rings. Generalized linear models were used to relate different variations of temperature and precipitation parameters, resulting into a diverse climate-growth relationships of different populations, while the composite population exhibited pronounced effect of temperature. We conclude that, I. azorica forms reliable annual tree-rings, which can be statistically related to climate, mostly temperature. However, there are differences among specific sites, thus the climate sensitivity depends on other site characteristics, such as soil and slope, but probable also to other ecological drivers, such as the competition, water drainage, among others. Diogo C. Pavão is currently supported by a PhD studentship grant (SFRH/BD/136336/2018) from Fundação para a Ciência e Tecnologia (FCT), Ministério da Ciência, Tecnologia e Ensino Superior. This research was also supported by the Azores Government - DRCT-M1.1.a/015/Funcionamento/2020 (CIBIO-A); by FEDER funds through the Operational Program for Competitiveness Factors - COMPETE and by National Funds through FCT - Foundation for Science and Technology under the (FCT) UIDB/50027/2020 (CIBIO) and (FCT) UIDP/50027/2020 (CIBIO). This work was also funded by FEDER in 85% and by Azorean Public funds by 15% through Operational Program Azores 2020, under the project AZORESBIOPORTAL – PORBIOTA (ACORES-01–0145-FEDER-000072). L. Borges Silva was supported by Azores Government-PRO-SCIENTIA/FRCT/2020/M3.2.a/ 001. J. Jevšenak was supported by the Aleksander von Humboldt postdoctoral fellowship and Slovenian Research Agency (P4–0107). info:eu-repo/semantics/publishedVersion