Objective To assess on the effect of the different catheterization on patients with oral poisoning gastric lavage systematically and objectively. Methods A computerized search of PubMed, the Cochrane Library, EMBASE, Springer Link, Science Direct,China Biology Medicine (CBM),China National Knowledge Internet(CNKI), Wanfang Data and VIP database was performed for relevant randomized controlled trials (RCTs) which investigated the effects of the oral intubation gastric lavage on patients with oral poisoning relative to nasogastric lavage, retrieval to January 2016, and back into the study of references. According to include and exclude standard to screening literature, literature which met inclusion criteria was selected for quality evaluation and data extraction. Meta-analysis and trial sequential analysis were performed by using Rev-Man 5.3 and TSA soft-ware to estimate the required information size (RIS). Results 13 studies incorporated into Meta-analysis including a total o 1 296 patients. Meta-analysis results showed that the oral intubation gastric lavage group was better than nasogastric lavage in shortening the time of intubation [MD=-9.05, 95% CI(-12.86--5.23), P=0.00], improving the rate of intubation for the first time [MD=1.36, 95% CI (1.14-1.62), P =0.00], mucosal bleeding complication [MD=0.11, 95% CI (0.04-0.64), P=0.010], nausea and vomiting [MD=0.60, 95%CI (0.37-0.98), P=0.04], kinking [MD=0.14, 95% CI (0.02-0.80), P=0.03], reflex cardiac arrest [MD=0.24, 95% CI (0.08-0.71), P=0.01] and asphyxia [MD=0.45, 95% CI (0.26-0.80), P=0.007], the difference were statistically significant. But no significant difference existed in gastric tube fall off. Conclusions The oral intubation gastric lavage could shorten intubation time of patients, improve the first time intubation rate and reduce certain complications. It suggests that the oral intubation be extensively applied to care patients with oral poisoning.