Although Mean Motion Resonances (MMRs) only reflect the orbital relations between part planets of some systems, the discovery of MMRs feature has promotes the study of the evolution of multi-planet systems. To better study orbital relations between all planets, we calculated planetary observation data of all multi-planet systems with the concept of ratio parameter and deviation rate. In this way, orbital relations between all planets of any system can be displayed in a clearer quantification way, including MMRs planets. Through comparing ratio parameters and counting deviation rates, we found more orbital features and summarized them into the Shared Rules between Planetary Orbits. The Shared Rules describe common regularities between planetary orbits, embodying the essence of logarithmic spiral. From the Shared Rules, we derived related equations and principles. We will show explanations. Although all systems are controlled by the same central gravitation, not every system clearly displays the Shared Rules because of varying disturbances and observation limitations. Calculations show, of the discovered 96 systems containing four and more exoplanets, 83 display the Shared Rules. Of the 335 period ratios consisting of 431 confirmed exoplanets of the 96 systems, 16.12% ratios show the absolute values of the deviation rates bigger than 40 per cent. Big deviation rates usually suggest some influences, imply planetary absence and migration, and affect the display of the Shared Rules. The Shared Rules can help to show planet migration and absence, calculate the orbits of migratory, disappeared and undetected planets, learn about the changes of planetary configurations, and study the evolution of multi-planet systems.