Objective: The objective of this study was to evaluate sex differences in recovery from concussion. This study compares the neurocognitive test performance of male and female concussed athletes two days post-injury to a group of healthy control athletes. Methods: A sample of 109 male and female high school and college athletes was evaluated two days post-injury using a computerized neurocognitive test battery (ImPACT) that is now in use by over 500 high school, college, and professional sports teams. Male and female concussed athletes were compared to a sample of non-concussed (control) athletes using Multi-Variate Analysis of Variance (MANOVA) with sex (male vs. female) and concussion status (concussed vs. control) serving as independent variables and the memory, reaction time, and processing speed composite scores from ImPACT serving as dependent variables. The concussed and control athletes participated primarily in American football, soccer, or ice hockey. Results: The MANOVA yielded a main effect for concussion status (Rao’s R = 4.92, df = 3,130, p = 0.002) indicating overall neurocognitive dysfunction in the concussed group compared to the control group. Differences between concussed and control athletes were observed on the memory (F = 7.67, p = 0.006), reaction time (F = 9.67, p = 0.002), and processing speed (F = 6.22, p = 0.01) composite measures of ImPACT. Both males and females performed equally poorly on post-concussive testing compared to non-injured controls. Conclusions: Concussed male and female athletes performed comparatively poorly on a computerized neurocognitive test battery at 2 days post-injury. The effect of sex was not significant, indicating no differences between male and female athletes in acute recovery from concussion.