A method for manufacturing a syringe barrel includes: providing a syringe barrel comprising a hollow body portion having an inner surface, the syringe barrel being configured such that a gasket is insertable into the syringe barrel and slidable on the inner surface of the body portion applying a non-reactive silicone oil having a viscosity in a range of 3000 cps to 30000 cps to the inner surface of the body portion by spraying the silicone oil with a coating amount rate of 0.02 mg/cm2 to 0.2 mg/cm2 and heating the silicone oil applied to the inner surface of the body portion in a state in which a liquid is not filled in the syringe barrel, without using a tool to spread or smooth the silicone oil.
