An ion analysis device includes: an ion source that ionizes an analyte in a liquid sample; an ion guide into which droplets and ions produced in the ion source are introduced, the ion guide having different outlets, one outlet being an ion outlet for the ions and the other outlet being a droplet outlet for the droplets; an ion analysis unit that analyzes ions ejected from the ion outlet; a droplet measurement unit that is placed on an axis of the droplet outlet, and measures the amount of droplets; and an analysis control section that compares the amount of droplets measured at the droplet measurement unit with a threshold.