The present invention aims to provide a transmission device that, in a communication system using multilevel modulation with 2^n levels (n being an integer greater than or equal to two), limits the run length to a predetermined value or less and guarantees DC balance.The transmission device, which transmits data to which 2^n amplitude modulation has been applied, separates data for transmission into n data sequences; encodes one of the n data sequences to guarantee run length, thereby generating a converted data sequence; generates an intermediate data sequence by either inverting or not inverting a specific data sequence so that, based on candidate data, the next output voltage guarantees DC balance; and applies 2^n amplitude modulation to n-bit symbols each of which has a bit in the intermediate data sequence as a most significant bit and bits in the remaining data sequences, excluding the specific data sequence, as subsequent bits.