The purpose of the present invention is to provide a viscoelastic composition having excellent operability, which is suitable for use in securing the field of view of an endoscope when opaque dark-colored liquid accumulates inside a canal and obstructs the field of view of the endoscope, the viscoelastic composition securing the field of view by pushing the liquid aside, and to provide a method for securing the field of view of an endoscope using the viscoelastic composition. The viscoelastic composition for securing the field of view of an endoscope comprises a substance having viscoelastic properties and water, preferably has a hardness of 550 N/m 2 or less, a viscosity (25°C) of 200 to 2,000 mPa·s, and a loss tangent of 0.6 or less, and more preferably has an electrical conductivity of 250 µS/cm or less. The method for securing the field of view of an endoscope comprises feeding the viscoelastic composition from a proximal part of the endoscope, through a channel, into a distal part of the endoscope.