To provide an inkjet head excellent in the stability of ejection of high-viscosity ink, and an image forming apparatus such as a printer equipped with the inkjet head.

Ink ejection pulses (first, second and third pulses) and a faint driving pulse (having the function of agitating ink by vibrating a meniscus) are pulses with reversed polarity with respect to a base voltage Vb, and the faint driving pulse is located behind the ink ejection pulses. When Tc represents a pressure resonance period in an ink pressure chamber, a time difference between fall times T1 and T3 of the ink ejection pulses and a rise time T4 of the faint driving pulse is set to be an odd multiple of Tc/2, and the pulse width of the faint driving pulse is set to be an odd multiple of Tc/2.