In healing and controlling diabetes mellitus in Indonesia, at this time insulin injections are usually carried out using a needle spuiit and insulin pen in the patient's skin area. In this research, a Portable Insulin Pump was designed to help people with diabetes mellitus control blood sugar to meet normal blood glucose concentrations. This tool is designed using an arduino uno microcontroller as a control panel (processor), a stepper motor that functions to produce linear movements periodically with a threaded rod as a linear drive (liquid booster on a syringe), 2x16 LCD as a display and a battery as a 12 volt DC voltage supply and 5 DC volts. This tool is equipped with an injection time timer by using a real time clock (RTC) module, manual mode injection speed of 10 units / minute, rotation speed of the manual stepper motor mode 21 RPM and speed when the bolus mode is 291 RPM. The data collection method used is measuring the suitability of injection doses using a measuring cup and measuring the suitability of injection time using a stopwatch. In the measurement of injection doses obtained an average value, the measurement of injection time obtained an average value of 1 milli / minute, the measurement of the maximum supply voltage obtained an average and a voltage of 8.5 VDC, then measurements of manual and auto mode RPM obtained an average of 21 RPM, and bolus mode obtained an average of 291 RPM. Function and feasibility test of tools conducted by respondents obtained a percentage of feasibility assessment as much as 78%, Experiment injection of the equipment carried out in mice with vitamin b of 4 units (4 ml) injected into mice obtained the results of the tool can be used for injection. From the results of data collection it can be concluded that the tool is feasible and can be used.