The effective storage time (i.e., storage life) of raw natural rubber (NR) was investigated with heat-accelerated storage aging combined with thermogravimetry (TG) and differential thermal analysis (DTA) method, as well as the heat aging life equation. The test results show that the effective storage time of raw NR can be estimated more conveniently in relatively shorter time by this method. It is found that the effective storage time of raw NR is associated with rubber processing technology and with ambient temperature during storage, but it has little relation with P-0 and PRI. At ambient temperature, the effective storage time of the natural-coagulated and biological-coagulated NR is obviously higher than the acetic acid-coagulated NR; the lower the ambient temperature, the longer the effective storage time. The effective storage time of the acetic acid-coagulated NR is 12.2-13.4 years at ambient temperature of 30 degrees C, 23.8-25 years at 25 degrees C, and 47.4-47.9 years at 20 degrees C. The effective storage time of the natural- and biological-coagulated NR is 13.7-15.2 years at 30 degrees C, 29.6-30.4 years at 25 degrees C, and about 62.5-65.8 years at 20 degrees C. (c) 2006 Wiley Periodicals, Inc.