Recently, low power ciphers that can be used in IoT devices have attracted the attention of many researchers. The power consumption of Midori is the lowest of all available ciphers. In hardware security, side-channel attacks pose a danger because they illegally analyze the secret key in a cryptographic device using the power consumption and electromagnetic waves generated during the device's operation. One type of side-channel attack that uses electromagnetic waves is called electromagnetic analysis. To examine the safety of future IoT devices, it is extremely important to investigate the resistance of Midori, an extremely low-power cipher, to electromagnetic analysis (tamper resistance). However, to our knowledge, no studies have reported on electromagnetic analysis against Midori. The present study proposes a method of electromagnetic analysis.