Abstract: MIMO radar imaging using ISAR technique combines the space sampling of MIMO radar and the time sampling of ISAR techniques, which can save many antenna elements and improve image resolution. However, there will be the nonequivalent relationship between the space sampling and time sampling, when parameters fail to be matched. By analyzing the effect of nonequivalent relationship between space and time in detail, this paper obtains the number and locations of false targets. Analytical formulas to calculate the peak to false ratio is deduced, and amplitude attenuation of targets is quantitatively analyzed. On this basis, further discussion gives some characteristics of images for targets in the special locations. Finally, simulations are performed to verify these analyses and formulas.