The utility model provides a blowout-preventing cap for oil pipes, which comprises a handle (1), a blowout-preventing cover (2), a connecting rod (3) and a screwed plug (4), and is characterized in that a through-hole for communicating the bottom end thereof with the lateral wall thereof is formed on the screwed plug (4); and the blowout-preventing cover (2) is mounted on the connecting rod (3). The blowout-preventing cap of the utility model has the advantages of simple structure and convenient use, and is capable of preventing the oil in the oil pipes from overflowing and spilling in all directions, thus providing convenience for construction and avoiding environmental pollution.