Abstract: Ultracold plasmas created by photoionizing a sample of laser cooled and trapped cold atoms, has extended the neutral plasma parameters by about two orders of magnitude, as the electron temperatures as low as 1 Kelvin. Previous studies focused on the study of the plasma free expansion and electron temperature evolution without a magnetic field. In this talk, I will present the first study of ultracold plasma dynamics in a magnetic field by using a newly developed time-of-flight projection imaging technique, such as plasma expansion and plasma instabilities.