A method of monitoring a semiconductor process is provided. The method includes preparing a process chamber including first and second electrodes spaced apart from and facing each other, and connecting the first electrode to a ground and connecting the second electrode to a radio frequency power source. An impedance in the process chamber is measured using a voltage value and a current value at the second electrode. The consumption amount of consumables in the process chamber is checked using the impedance. Varied process conditions are adjusted within an initial set range.