Objective:To analyze the emergency sample testing time of VITROS XT 3400 biochemical testing system and evaluate its testing method.Method:Retrospective analysis was conducted on all specimens from the emergency laboratory department of our hospital from August 2020 to July 2022, including albumin(Alb), total protein(TP), aspartate amino transferase(AST), alanine aminotransferase(ALT), creatinine (Cr), blood Urea Nitrogen(BUN), calcium (Ca) and glucose (Glu) to calculate the utilization rate of composite dry slide projects. A total of 635 serum samples were collected from emergency patients in our hospital from June 20 to 26, 2022, and the difference in sample testing time was compared between VITROS XT 3400 (composite dry tablets) group and VITROS 4600 (ordinary dry tablets) group during low and peak periods. The difference in replacement reagent and daily maintenance time was also compared between the two groups.Result:The pairing rates of three projects (Alb-TP, AST-ALT, Cr-BUN) are all over 99%. The detection time of the VITROS XT 3400 group samples was significantly shorter than that of the VITROS 4600 group [(945±477) s compared to (1 101±567) s, t=20.378, P<0.001]. The detection time of the VITROS XT 3400 group samples during high and low peak periods was significantly shorter than that of the VITROS 4600 group [low peak period ( n=322): (857±567) s compared to (905±528) s, t=13.102, P<0.001; peak period ( n=313): (1 035±400) s compared to (1 303±492) s, t=21.876, P<0.001], The reagent replacement time of the VITROS XT 3400 group was significantly shorter than that of the VITROS 4600 group [(690±127) s vs (869±152) s, t=11.470, P<0.001]. There was no statistically significant difference in daily maintenance time between the VITROS XT 3400 group and the VITROS 4600 group [(1 771±123) s vs (1 765±95) s, t=0.238, P=0.834]. Conclusion:XT 3400 has faster detection speed when using the composite dry slides, which can better alleviate the detection pressure during peak hours.