This paper presents a study the effect of coil turn numbers on the magnetic and effective magnetic energy of a solenoid injector. To achieve this goal, a magnetic injector simulation model is setup based on the Maxwell software. From this simulation software, the researchers are able to investigate the effect of input parameters on the solenoid injector magnetic and effective magnetic energy. Those input parameters are: coil turn numbers, coil cross section area, input current and input voltage. In scope of this research, the effect of coil turn numbers on the injector performance will be completely discussed. The results of the research show that: the coil turn numbers have sensitive effect on solenoid injector magnetic and effective magnetic energy. When the coil turn numbers increase form 40 turn to 80 turn, the injector magnetic increases form 0.167 T t 0.33 T, improved 100%. The injector effective magnetic energy increases form 4.86 KJ/m3 to 19.6 KJ/m3, improved 300%.