The invention provides a series oil cylinder reversing control method and device and a concrete pumping system. The reversing control method includes the steps that position signals of a first piston of a first oil cylinder are acquired; position signals of a second piston of a second oil cylinder are acquired; when the first piston reaches a first preset position or a second preset position or when the second piston reaches a third preset position or a fourth preset position, series oil cylinders are triggered to reverse. By the adoption of the reversing control device, under the condition that no external hydraulic system pipeline is arranged, the volume of oil liquid in a communicating cavity is adjusted through U-shaped pipes of an existing oil cylinder, normal reversing can be still conducted when the volume of the oil liquid is not normal, adjustment of the volume of the oil liquid in the communicating cavity continues to a next period for conduction, the phenomenon that the pistons impact on the front ends or the rear ends of the oil cylinders due to the fact that the volume of the oil liquid in the communicating cavity is not normal is avoided, the service life of the oil cylinders is prolonged, and reliability of the system is improved.