The biggest challenge of laser forming technology is how to fulfill the requirements of the workpiece shape and size. Equivalent length-based criterion algorithm is proposed for a scheduled line single surface. Scanning path is planned within the given shape error, according to the way of equivalent length and different bending angles. Based on the algorithm requirement, the relationship between process parameters and bending angles is researched. During the experiments, bending angles are measured by a real-time monitoring system. The experimental results reveal that the laser bending angles are linearly proportional to the number of irradiations and laser line energy in a certain parameter range. Then, the experiments according to scanning paths verify the applicability of the proposed method.