  As with the laser interferometer gravitational-wave observatory (LIGO), the
matched filtering technique will be critical to the data analysis of
gravitational wave detection by space-based detectors, including LISA, Taiji
and Tianqin. Waveform templates are the basis for such matched filtering
techniques. To construct ready-to-use waveform templates, numerical relativity
waveforms are a starting point. Therefore, the accuracy issue of numerical
relativity waveforms is critically important. There are many investigations
regarding this issue with respect to LIGO. But unfortunately there are few
results on this issue with respect to space-based detectors. The current paper
investigates this problem. Our results indicate that the existing numerical
relativity waveforms are as accurate as 99% with respect to space-based
detectors, including LISA, Taiji and Tianqin. Such an accuracy level is
comparable to that with respect to LIGO.
