The thermal decomposition of calcium citrate tetrahydrate in dynamic air or dry nitrogen has been studied thoroughly. Thermal events encountered throughout the decomposition range (room temperature to 1000-degrees-C) have been monitored by TG, DTA and DSC. The encountered events have been characterized by analysing the decomposition solid products using X-ray diffractometry, IR spectroscopy and scanning electron microscopy (SEM). Non-isothermal kinetic and thermodynamic parameters (A, k, DELTAE, DELTAH, C(p) and DELTAS) have been determined. The results show that Ca3(C6H5O7)2 . 4H2O dehydrates in two successive steps at 60-140-degrees-C and 140-190-degrees-C each involving release of two moles of water. The ultimate decomposition product has been found to be CaO which formed above 640-degrees-C in air or dry nitrogen flow. SEM examinations indicate the formation of fusion nuclei accompanying the second dehydration step. Decomposition pathways in air and nitrogen are proposed.