In a previous study, we developed a method for assessing building damage at the district level in markedly damaged areas using satellite-derived synthetic aperture radar (SAR) data and conducted a coherence analysis of urban areas. We previously evaluated the relationship between the average coherence within a 200-m mesh and degree of building damage in Mashiki, Kumamoto Prefecture, Japan, using L-band ALOS-2 PALSAR-2 data obtained before and after the Kumamoto earthquake. Our findings indicated a significant negative correlation between these parameters. Currently, C-band Sentinel-1 provides global coverage at a high observation frequency. However, previous studies have not sufficiently evaluated the effects of differences in acquisition conditions. Therefore, we aimed to investigate how acquisition conditions affect the relationship between coherence and the building damage rate using images captured by Sentinel-1 C-SAR during the Kumamoto earthquake. The results showed that coherence tended to decrease as the damage rate increased but the correlation was not significant. The difference in coherence per 10% of the building damage rate was less pronounced compared with the results obtained from ALOS-2. Our findings also indicated that the effects of the pre-earthquake acquisition dates and the baseline were less than those of the orbit direction and incidence angle.