The role of non-steroidal anti-inflammatory drugs (NSAIDs) and acetylsalicylic acid in the occurrence of diverticular bleeding (DB), complicated diverticulitis (CD), and acute diverticulitis (AD) is not yet defined. Update a systematic review and meta-analyses of case-control and cohort studies to evaluate the association between NSAIDs or acetylsalicylic acid with DB, CD, or AD. The study included were identified through MEDLINE, Scopus, Web of Science, and Cochrane Library databases. Sizes were pooled across studies to obtain the overall effect size. A random-effects model was used to account for different sources of variation among studies. Odds ratio (OR) with 95% confidence interval (CI) was used as a measure of effect size. Thirteen studies were included in the systematic review and meta-analysis. NSAIDs and acetylsalicylic acid use were associated with an increased risk of DB (OR: 6.90, 95% CI 3.86 to 12.35, P ˂ 0.00001, and OR 2.84, 95% CI 2.19 to 3.67, P < 0.00001, respectively). NSAIDs and acetylsalicylic acid use were also associated with increased risk of CD occurrence (OR 3.13, 95% CI 1.73 to 5.68, P = 0.0002, and OR 1.49, 95% CI 1.02 to 2.17, P = 0.04, respectively). The only study found about AD occurrence showed that NSAIDs use was not associated with AD and acetylsalicylic acid use had a low risk of AD. NSAIDs and acetylsalicylic acid significantly increase the risk of DB and CD. Further studies are needed to clarify the role of NSAIDs and acetylsalicylic acid in AD. However, increasing evidence suggests caution in the use of such medications in patients with colonic diverticula.