Objectives: This study conducted a meta-analysis to examine the effectiveness of computer and Internet training interventions intended to reduce loneliness and depression in older adults. Methods: Searches were performed to retrieve studies that had been published in peer-reviewed journals from January 2001 to July 2012 and written in English or Korean from PubMed, CINAHL, Scopus, the Cochrane Library, PsycINFO, KoreaMed, KMbase, KISS, MEDLIS, and RISS. We used combinations of the keywords for population, intervention, and psychosocial problems. A meta-analysis was employed to summarize the findings of studies on computer and Internet interventions for older adults. An overall mean weighted effect size for each outcome was calculated, and Q statistics were used to test the heterogeneity of variance in the effect sizes of the selected studies. Results: As the Q statistics revealed heterogeneity, random effects models were chosen for the meta-analysis. The overall mean weighted effect size for loneliness from five studies was statistically significant for decreased loneliness (Z = 2.085, p = 0.037). However, the overall mean weighted effect size for depression from five studies was not statistically significant (Z = 1.528, p = 0.126). Conclusions: These results suggest that computer and Internet programs were effective in managing loneliness among older adults. Therefore, further computer-mediated social support should be considered to help manage loneliness in this population.