Purpose: Ginger (Zingiber officinale) has been widely used as an antiemetic agent. This systematic review was aimed at evaluation of the effect of dried ginger powder supplementation on improvement of nausea and vomiting associated with early pregnancy or motion sickness. Methods: We searched Pubmed, Cochrane, Science Direct, and KISS (Korean studies Information Service System) using keywords such as ginger or Zingiber officinale in combination with nausea, vomiting, motion sickness, or pregnancy, published in March 2013. Results: The strength of the evidence was evaluated on the selected 12 RCTs (randomized controlled trials). Eleven trials including 2,630 subjects showed that supplementation with dried ginger powder resulted in significant improvement of nausea or vomiting related to early pregnancy or motion sickness. Among the nine studies including 809 women in early pregnancy before 20 weeks of gestation, ginger supplementation was superior to placebo in five studies (n = 305), and as effective as positive control (vitamin $B_6$ or dimenhydrinate) in four studies (n = 504). Ginger intake significantly reduced the episodes or severity of vomiting related to motion sickness compared to placebo or showed the same effect as several antiemetic drugs in two studies (n = 1,821). Conclusion: Our findings added evidence indicating that ginger powder supplements might improve the symptoms of nausea or vomiting related to early pregnancy or motion sickness without significant adverse events.