Approximately 15% to 20% of the older adult population worldwide are affected by mild cognitive impairment (MCI). It is characterized by deterioration in cognitive function including memory, attention, executive function, visuospatial, or language ability. This condition leads to dementia. Therefore, cognitive training is needed to enhance cognitive function. Most cognitive training programs are conducted in conventional way. Virtual reality (VR) is a potential tool to improve cognitive function. VR is a computer-generated simulation of three- dimensional environment that gives the users a  sense  of  presence. This meta-analysis study aimed to determine the effectiveness of VR training in improving cognitive function of older adults with MCI in comparison to conventional training. A systematic search for randomized control trials in five electronic databases yielded  18 studies with 858 participants. A random-effects analysis estimated medium effect sizes for VR  training  compared  to  conventional training  in  overall   cognitive   function   outcomes   (g   =   0.38,   95% CI 0.04;0.71) and global cognition (g = 0.73, 95% CI 0.29;1.17). A comparison of VR and conventional  training  did  not  show significantly different effect sizes in memory (g = 0.20, 95% CI - 0.39;0.79), executive function (g = -0.26, 95% CI -0.83;0.31), and visuospatial (g =  0.45, 95% CI -0.21;1.10). These results indicate that VR training is more effective than conventional training in improving overall cognitive function and global cognition of older  adults  with MCI. On the other hand, VR and conventional training have equal effectiveness in improving memory, executive function,  and visuospatial abilities of older adults with MCI.