The aim of this work was to study the effects of different kinds of dispersants, grinding time and storage time on the dispersion stability of UV inkjet colorants. Nine colorants samples were prepared by using different dispersants (685,CH-13,the mixture of 685 and CH-13), predispersing, and changing grinding time (60, 75, 90 min) as well as storage time (2, 12, 20 d). The particle size and particle distribution were measured and analyzed. The dispersion result of dispersant 685 was good, and good dispersion stability was obtained when the grinding time was 75 min and the storage time was 2 d. The UV inkjet colorants made of dispersant 685 had the best dispersion stability, and the optimal grinding time was 75 min. The colorant stability and storage time showed a negative correlation.