Shalaii Cave is a closed system cave that contains old and active speleothems. It is located on the northeast limb of the Ashdagh anticline in Sangaw district in northeastern Iraq. The study presents new data on cave monitoring and the geochemistry of stalagmite archives relevant for the palaeoclimate of Iraq. An extensive cave monitoring program was conducted from June 2014 to March 2015, which included analyses of cave air temperature, relative humidity, cave air, dripwater, and modern calcite precipitates on glass slides. Physical parameters were measured monthly and continuously using data loggers and meteorological data; rainwater and dripwater samples were acquired for stable isotope analyses and hydrochemistry analysis. Stable isotopes of oxygen and carbon and absolute dating of U/Th series dating was used to determine palaeoclimate conditions. The microclimate of Shalaii Cave during the studied period (June-2014 to March-2015), the average temperature at the entrance point and inside the monitored cave was 17.05 °C and 20.18 °C respectively. The relative humidity at the entrance point and inside the cave was 66.6% and 100% respectively. Eleven samples of dripwater and five samples of rainwater were acquired for isotope analyses and thirteen samples of dripwater for hydrochemical analysis. From the environmental isotopes analysis (2H and 18O), all water samples fall between the global meteoric water line (GMWL) and Sangaw meteoric water line (SMWL). The precipitation samples plot well above the GMWL. The mechanism of recharge is direct recharge. Two stalagmites (SHC-01 and SHC-02) were sampled from the cave. The first sample (SHC-01) is dated from 1012 ± 42 to 494 ± 29 yr B.P. and the second sample (SHC-02) dates between 8025 ± 38 to 6977 ± 219 yr B.P. Oxygen and carbon isotope results show that there are two climate conditions for palaeoclimate reconstruction in the Sangaw district. Conditions were generally wetter and colder during 8025 ± 38 to 6977 ± 219 yr B.P. than current conditions; from 1012 ± 42 to 494 ± 29 yr B.P., drier and warmer conditions prevail, more similar to today. •Analysis of speleothems is significant for palaeoclimate determination.•This paper presents new data on cave monitoring from Kurdistan Province of Iraq.•Stable isotopes, and cave parameters integrated to understand behavior of the cave•Carbon and oxygen isotopic values are useful for climatic proxies.•Uranium-thorium dating is a good tool for age determination of the speleothems.