At present

research on secure multi-party computation is of great interest in the field of information security.Privacy-preserving intersect-determination of two polygons is a special secure multi-party computation problem

it can be applied in many fields

such as military field and commerce field.Scalar products protocol plays an important role in the known methods of privacy-preserving intersect-determination of two polygons

however

the current scalar products protocols aren't fit for the determination algorithm on the security and the complexity at the same time.In this paper

a protocol for privacy-preserving intersect-determination of two line segments is developed and a probability algorithm for privacy-preserving intersect-determination of two polygons is presented.Both of the theoretical analysis and the experiment results show that the new algorithms are more efficient than the current algorithm.