Plasma propulsion systems have become the most attractive systems for satellite engines due to their simplicity and reliability. This research was carried out to manufacture an electrothermal pulsed plasma thruster system using a polyester capillary. This study includes a measurement of ablated mass with different input voltage values and with increasing in the number of shots. It was found that by increasing the input voltage from 1.5 kV to 4 kV, the ablated mass increases from 120.6 μg to 432.6 μg. The experimental results were compared to the theoretical data obtained from the ETFLOW model; the calculated ablated mass increased from 136 μg to 447 μg, which is in good agreement with the measured results. Also, the model was used to study the behavior of some physical parameters with discharge time, such as plasma density, velocity, and temperature. Finally, the exit velocity was calculated as a function of peak current