The application of general circulation models (GCMs) could improve our understanding of climate forcing. Furthermore, longer climate records spanning a wider range of climate states could help in assessing the skill of the models for simulating climates different from the present. We first attempt to find a way to combine proxy records which are affected by different seasonal temperatures, and then present a large-scale temperature reconstruction over the last millennium for China by combining the Beijing stalagmite layer series and the Qilian tree ring sequence to compare with the GCM-based ECHO-G simulated millennial temperature record for China. The correlation coefficient between the simulated and the reconstructed temperature records is 0.61 based on a 31-year running mean (exceeding P < 0.01). An asymmetrical V-like low-frequency variation shown both by the combined proxy record and the simulated series is the major long-term pattern in the last millennial temperature in China, suggesting that solar irradiance as well as greenhouse gases could explain much of the low-frequency variations in the climate. However, there still exist high-frequency discrepancies between the two time series, which may be due to (1) the overestimated climatic effect of volcanoes within the GCM and/or (2) proxies which are not sensitive enough to respond to the volcanic eruptions. Copyright © 2009 John Wiley & Sons, Ltd.