The present invention provides a blood coagulation promoter capable of exerting both excellent blood coagulation promoting ability and excellent blood clot detaching ability, and a blood collection tube accommodating the blood coagulation promoter.The present invention provides a blood coagulation promoter which includes a hardly water soluble polyoxyalkylene derivative a partially saponificated polyvinyl alcohol at least one substance selected from the group consisting of adsorptive inorganic substances and hydrolases capable of hydrolyzing a bond between Arg and an arbitrary amino acid reside and/or a bond between Lys and an arbitrary amino acid residue in a peptide chain a polyvinylpyrrolidone and preferably a water-soluble silicone oil, and a blood collection tube in which the blood coagulation promoter is accommodated in a tubular vessel having a bottom.
