Numerical cases are studied for the behaviors of two dimensional classical and pulsating jet in crossflow (JICF) with Reynolds number 100. The corresponding flow characteristics of two dimensional JICF are presented by k-ε model in this paper in the range of velocity ratio r 1 ≤ r ≤ 4. Flow characteristics of vortex structure for two dimensional classical JICF have been analyzed first. The investigated vorticity field shows that the JICF falls into the turbulent flow with the increasing velocity ratio quickly. A vortex action is formed in the leeward side. The streamline field for the classical JICF have been obtained computationally and analyzed. The analysis of two dimensional pulsating JICF assumes the vorticity field at various velocity ratios, in which the ejected jet is enclosed by the fixed Strouhal number. The following analysis assumes the stream fields based on the same cases of the analyzed vorticity field. Vortex action area is also existing in the two dimensional pulsating JICF. Finally, the contrast of pulsating JICF with different Strouhal numbers have been obtained computationally and analyzed in detail to reveal the differences and connections between the pulsating JICF with different Strouhal numbers.