Miimo goes on sale next year, only in Europe, where spacious lawns are often enclosed in gates, targeting 4,000 unit sales a year.
The machine, which looks a bit like iRobot Corp.'s Roomba vacuum cleaner, continuously shaves about 3 millimeters (0.12 inches) off the grass, manoeuvring itself on slopes. It won't break potted plants, goes to charge itself on its own and won't wander off.
Honda robots, like its Asimo walking and talking robot, have sometimes been criticized as impractical toys.
Honda said Tuesday that Miimo will sell for 2,100 euros ($2,600) to 2,500 euros ($3,000).