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This paper proposes an overvoltage suppression method using an LCR filter and PWM technique for SiC inverter systems with cable modeling. Overvoltage occurs not only from fast switching but also from voltage reflections caused by impedance mismatches in SiC-based inverter systems with long transmission lines. These reflections lead to excessive voltage at the motor terminals. To suppress such overvoltage, software-based approaches such as the pulse elimination technique (PET) and the maximum minimum pulse technique (MMPT) have been investigated. However, these methods distort the voltage waveform and degrade output performance because they forcibly constrain the reference voltage. To address this issue while preserving output characteristics, a hardware-based solution is proposed. The proposed LCR filter is designed using high-frequency cable modeling to suppress overvoltage induced by fast switching. In addition, the damping resistance of the LCR filter is matched to the cable impedance, which further attenuates the reflected overvoltage. Its effectiveness was verified through simulations and experiments, demonstrating significant improvements over software-based techniques.