Disclosed are a system, a device, and a method of a lubricant applicator device to be used with an insertion tube of an endoscope. The lubricant applicator device includes a tubular member to surround a portion of an endoscope insertion tube such that the tubular member is extendable over the portion of the endoscope insertion tube to snugly surround the portion of the endoscope insertion tube. An enlarged bulbous region adjacent to a distal end of the tubular member is pre-filled with a gel material that is releasable onto a surface area of the endoscope insertion tube encompassed by the enlarged bulbous region. A handle region adjacent to a proximal end of the tubular member that extends from the enlarged bulbous region provides a non-slip exterior surface to enable a human hand of an operator to grasp the handle region and manipulate the endoscope insertion tube.