The invention discloses a nuclear power station pipeline weld inner wall grinding robot, which comprises a sealing unit, a grinding unit, a driving unit, and an electric element unit. The sealing unitcomprises a first round table and a rubber sealing plate arranged on the first round table; the grinding unit comprises a rotary holder and a grinding device arranged on the rotary holder; the driving unit is used for driving the grinding unit to enter and exit a pipeline; and the sealing unit, the grinding unit, the driving unit and the electric element unit are connected in a bending way. Compared with the prior art, the nuclear power station pipeline weld inner wall grinding robot provided by the invention has the following advantages that multiple functions of automatic grinding, polishing, cleaning and nondestructive testing of a steel-made pipeline weld inner wall are realized, the problem that the steel-made pipeline weld inner wall cannot be ground is solved, a turning and climbing problem of the robot on the pipeline inner wall is solved, the problem of weld stress concentration is solved, a heat fatigue effect is eliminated, the weld quality is ensured, and the weld potential quality hazard is eliminated.