As one of non- traditional stable isotopes, calcium isotopes are attracting increasing attention from international geologists. Calcium is an important metal element because it is one of the main petrogenetic elements, as well as an important nutrient element in organisms. Calcium is widely distributed in all spheres of earth systems, thus studying the geochemical behavior of calcium isotopes could be very helpful in improving understanding of all kinds of biological and geological processes. Calcium isotope ratios are widely measured by adopting thermal ionization mass spectrometry (TIMS) or multi- collector inductively coupled plasma- mass spectrometry (MC- ICP- MS) and are expressed as δ44/40Ca or δ44/42Ca, respectively. Variations of δ44/40Ca in nature are mainly from -2. 0‰~+6. 75‰, spanning a limited range of 8. 7‰. This paper systematically introduces some achievements on calcium isotopic method for sample dissolution, chemical separation, mass spectrometry measurements along with calcium isotope fractionation in high and low temperature geological processes and its geological application. Especially, this paper also gives a detailed review of the application of calcium isotopic method to carbonatite and associated silicate rocks on different aspects as its scientific value, calcium isotopic compositions and the main understanding obtained. It focusses on the effects of radiogenic 40Ca, mantle partial melting/fractional crystallization, crustal assimilation, recycling of old subducted carbonate, hydrothermal alteration, depth of origin of the magma on the calcium isotopic compositions of carbonatite and associated silicate rocks. By systematically comparing the research results of lithium, magnesium and calcium isotopes of carbonatite and associated silicate rocks, it is suggested that a combined tracer of multiple isotopes should be carried out. Due to the similarities and differences in different isotopic systems, a combination of multiple isotopic systems can effectively provide complementary advantages, which will be a significant progress in the isotopic geochemistry.