A liquid condiment container comprising: a bottle; and a cap, the liquid condiment container being to be filled with a condiment, which is a liquid condiment having a viscosity of from 5 Pa·s to 500 Pa·s, an initial volume of the liquid condiment container being from 100 cm 3 to 700 cm 3, the bottle including a mouth, a body, and a bottom, the mouth being a portion to which the cap is attached, the bottom having an outermost edge that serves as a ground portion in an upright state with the mouth being positioned upward, the body including a flat shape portion in horizontal transverse section in the upright state, the flat shape portion having a short axis and a long axis that are orthogonal to a center axis of the bottle, the body having a front surface and a rear surface that cross the short axis, the bottle having a single layer structure made of a low-density polyethylene as a main component or a multilayer structure including one or more layers made of a low-density polyethylene as a main component, the one or more layers made of the low-density polyethylene as the main component in the multilayer structure having a total thickness of 80% or more of a thickness of the bottle, characterized in that the liquid condiment container satisfies y/x 2/3 of from 0.35 to 0.65, where x (cm 3) represents the initial volume, and y (g) represents a basis weight of the bottle excluding the mouth, the bottle has an inner pressure of from -1.0 kPa to -3.0 kPa after 30 seconds from suction of air in the bottle by 10% of the initial volume from a state in which the bottle is completely filled with the air and with a temperature at the time of measurement of 25°C, and the low-density polyethylene is produced by a high pressure method and has a bending modulus of from 130 MPa to 370 MPa based on a JIS K6922-2 method. a bottle; and a cap, the liquid condiment container being to be filled with a condiment, which is a liquid condiment having a viscosity of from 5 Pa·s to 500 Pa·s, an initial volume of the liquid condiment container being from 100 cm 3 to 700 cm 3, the bottle including a mouth, a body, and a bottom, the mouth being a portion to which the cap is attached, the bottom having an outermost edge that serves as a ground portion in an upright state with the mouth being positioned upward, the body including a flat shape portion in horizontal transverse section in the upright state, the flat shape portion having a short axis and a long axis that are orthogonal to a center axis of the bottle, the body having a front surface and a rear surface that cross the short axis, the bottle having a single layer structure made of a low-density polyethylene as a main component or a multilayer structure including one or more layers made of a low-density polyethylene as a main component, the one or more layers made of the low-density polyethylene as the main component in the multilayer structure having a total thickness of 80% or more of a thickness of the bottle, characterized in that the liquid condiment container satisfies y/x 2/3 of from 0.35 to 0.65, where x (cm 3) represents the initial volume, and y (g) represents a basis weight of the bottle excluding the mouth, the bottle has an inner pressure of from -1.0 kPa to -3.0 kPa after 30 seconds from suction of air in the bottle by 10% of the initial volume from a state in which the bottle is completely filled with the air and with a temperature at the time of measurement of 25°C, and the low-density polyethylene is produced by a high pressure method and has a bending modulus of from 130 MPa to 370 MPa based on a JIS K6922-2 method.