The TG, DTG and DTA curves of curcumin(I) have been recorded in static air and inert dynamic argon atmosphere over the range between ambient temperature and 600~176 using a Netzsch thermal analyser STA 429. Careful examination of these curves reveals appreciable differences in the behaviour of I under either atmospheres, which are easily recognized by comparing the profiles of their thermal curves, particularly in the melting point, thermal stability of intermediates, percent weight loss and exothermieity of the chemical processes. Gaschromatographic analysis of volatile pyrolysates trapped during thermal analysis indicates the formation of (CH3)2CO, CH3COH and C6HsOCH2COOH (phenyl oxyacetie acid). However, in static air CO2 and H20 were identified as well. X-ray diffractometry reveals the formation of amorphous carbon as a final product in argon and a mixture of amorphous carbon and graphite in air. It seems that the relatively high mass of argon plays an important role in the reactions and stability of intermediates. In either atmospheres curcumin is thermally stable up to 249~ with m.p. of 176.4~176The unique shape of the DTA curve of I could be used for its identification.