Privacy-preserving determination of spatial relationship belongs to spatial geometry problem in secure multiparty computation, which is significant to confidential business, engineering, military, etc. However, most existing schemes transform the original problem into the distance problem or the correspondingly proportional data problem, which makes the computation complexity high and the application range being limited. To deal with these problems, first, the original problem is transformed into whether a point is the solution of equation. Based on the technique, a simple and efficient scalar product protocol is adopted to determine five spatial relationships all at once: point and line, point and plane, line and line, line and plane, and plane and plane. In addition, the security of the proposed protocol is proved with simulation paradigm. The proposed scheme does not employ any public key encryption algorithm so as to achieve the information security. The analysis indicates the trick transformation makes the proposed scheme higher efficient and more applicable than the known schemes.