In this paper the interference factors of digital fluid observation data in Gansu province were systematically analyzed. According to analyzing the observation data, we found that the majority of interference factors were caused by equipment failures, rarely by human factors. The data of water level and water temperature were mainly disturbed by the equipment failure, voltage transient instability (or struck by lightning), invalid data, and so on. The quality of degasser-extractor devices of gas radon (gas mercury) played a decisive role in digital gas observation. Besides, contamination of scintillation chamber, gas circuit's blockage or leakage, as well as instability performance of Instrument, voltage instability and human factors, may cause notable interference. Some other factors can also cause abnormal changes of observed value.