The invention relates to an in-vitro 
diagnostic reagent for a homogeneous method of low-density 
lipoprotein cholesterol (LDL-C) of serum, wherein the in-vitro 
diagnostic reagent is capable of being widely applied to the technical field of 
medicine and 
biochemistry and is characterized in that the in-vitro diagnosis is carried out by means of a method comprising the following steps of: step one, selectively 
cracking chyle particles (CM), 
very low density lipoprotein cholesterol (VLDL-C) and 
high density lipoprotein cholesterol (HDL-C) within the serum by using a group of surfactant comprising trimethyl-beta-
cyclodextrin, 
ethylene oxide octadecyl amine, 
poloxamer F88 and Brij-58, then generating 
hydrogen peroxide (H2O2) during the catalytic reaction of 
cholesterol esterase (COE) and 
cholesterol oxidase (COD), and then discomposing the H2O2 by means of a 
chemiluminescence clearing 
system of 
hydrogen peroxide, wherein the LDL-C particles within the serum are still kept perfectly at the moment; step two, reacting the LDL-C by catalyzing with the COE and the COD under the effect of TritonX-100 so as to generate H202, then promoting a 
chemiluminescence quantitative 
system to produce 
chemiluminescence by catalyzing the H2O2 with POD, and quantitating the LDL-C after measuring 
luminous intensity. The measuring 
reagent provided by the invention has the advantages that the sensitivity is high, the capacity of resisting disturbance is strong, the purpose for detecting the LDL-C of serum in batch is realized on a microporous plate chemiluminescence apparatus by measuring chemiluminescence intensity, and the 
reagent is suitable for the application in clinical laboratory.