Plant phenology is an important indicator of ecosystem response to climate change. Most of the previous studies used the phenological observation data from the representative sites to investigate the phenological characteristics and its responses to climate change. Whether the phenological changes and their sensitivity to temperature are consistent among different sites of the same climatic region needs further exploration. This study selects Xi'an and Baoji, which are distributed at the Fen-Wei Plains climatic region with a humid and temperate climate, as the study area. Using the data of the first flowering date (FFD) and end of flowering date (EFD) of 21 woody plants in Xi'an and Baoji from China Phenological Observation Network, the interannual change and temperature sensitivity of flowering phenology were compared at different sites during 1987-2016. The results showed that the FFD and EFD of most species advanced in Xi'an and Baoji over the past 30 years. For most species, the trend of FFD in Xi'an (mean: -0.57 days/year) was significantly stronger than that in Baoji (mean: -0.29 days/year), but there was little difference in the trend of EFD between the two sites. Except for Lagerstroemia indica and Jasminum nudiflorum, the temperature sensitivity of the FFD and EFD for other species presented no significant difference between the two sites. Thus, the phenological changes at a single site cannot reflect the phenological changes in the whole climatic region, because the changes in FFD always showed significant discrepancies among different sites due to divergent changes in temperature. However, the temperature sensitivity of FFD and EFD calculated at a single site could well reflect the plant phenology-climate relationship at other sites in the same climatic region. Our study could provide a scientific basis for the analysis of regional phenological changes and responses to climate change using phenological observation data from the limited sites.