The Toyota Mark X ZiO is a CUV manufactured by Toyota and introduced in 2007. It replaces the Toyota Opa MPV, and is exclusive to Toyota Japan dealerships Toyopet Store, sold alongside the Toyota Mark X sedan.

The "4+Free" concept allows for a wide range of interior configuration.[context?][further explanation needed]The ZiO's "three mode" cabin can accommodate from four to seven passengers. In "personal sedan mode," a tonneau board with dual tonneau covers creates a sedan like vehicle. Stow the tonneau board and covers, and the "active wagon mode" creates a large cargo space in the rear. The "friendly minivan mode" adds seating for more passengers by raising the third-row seats in the cargo space. The name "ZiO" is an acronym to suggest its spaciousness and cargo capacity, meaning "Zone in One". It is similar in concept to but does not share a platform with the Venza.

For the first year of production, it won the Good Design Award given by the Japan Industrial Design Promotion Organization. According to Japanese vehicle regulations, the Mark X ZiO is classed as a normal-size vehicle.

The Mark X ZiO shares few features with the Mark X besides the name. The ZiO chassis is derived from the Auris. The 2.4 L ZiO is available in front-wheel drive (ANA10 chassis code) or four-wheel drive (ANA15 chassis code) with the 2AZ-FE motor and Continuously variable transmission (CVT). The 3.5 L ZiO is available in front wheel drive only (GGA10 chassis code) with the 2GR-FE motor and 6-speed automatic transmission. G-BOOK was added to the list of optional features.