[Objectives]  To clearly define the tolerance of adult Tetranychus cinnabarinus (Boisduval) to submersion in water, and provide a theoretical basis for evaluating the effect of rainfall on Integrated Pest Management of this pest. [Methods]  The proportion that sank, water survival, and leg sway frequency, of adult T. cinnabarinus, were determined using the slide dipping method and video technology. [Results]  The proportion of mites that sank was significantly higher when these had fed on cotton leaves for 5 d (92.79%±0.55%) compared to those that had fed for just 2 d (42.72%±2.37%). The average survival time in water of 3 day old male (297.7±7.4) min and female (297.4±16.1) min adults was not statistically different. The shortest survival times recorded for 3 day old male and female adults were, respectively, 45 min and 48 min. Immersion for about 300 minutes was sufficient to kill half of all 3 day old male or female adults. The longest survival time in water of 3 day old male and female adults were 856 min and 773 min, respectively. The distribution of mortality among male and female adults was uneven in time. In the process of death, adult T. cinnabarinus generally displayed a reduction in leg swing frequency. The duration of leg swinging behavior was not continuous. [Conclusion]  Adult T. cinnabarinus have some capacity to tolerate submersion in water.