The invention discloses seaborne digital intermediate frequency transmitting equipment comprising a signal modulation module, wherein an output end of the signal modulation module is connected with a transmitting antenna after sequentially passing through a power amplification module and an antenna tuning module. The signal modulation module comprises a DSP processor for mapping a load data part after the original data is subjected to LDPC encoding, and meanwhile adding into pilot frequency data to form an OFDM frequency domain frame; and an FPGA processor for receiving OFDM frequency domain frame data from the DSP processor, acquiring OFDM time domain frame data after discrete Fourier transform, inserting a cyclic prefix to perform upsampling and shaped filtering, and at last converting the data into an analog signal by DAC and then sending to the power amplification module. The digital intermediate frequency transmitting equipment is adaptively adjusted, can transmit information under different modes and rates, effectively reduced interference between carriers and improves spectrum efficiency, and meets the requirement of adaptively transmitting different formats of seaborne security information, documents and electronic charts.