This paper describes a brief description of Orthogonal Frequency Division Multiplexing (OFDM) waveform design and parameter for submarine radars. The radar works when the submarine is floating on the sea surface and it uses a radio frequency signal to detect multiple moving objects in the surrounding area. The OFDM parameters discussed here are including the carrier frequency, number of sub-carriers, number of OFDM symbols and the frequency spacing between subcarriers. By varying those parameters value to see how significant are their impact on radar performance, includes its maximum unambiguous range, maximum speed of the target and also its range and speed resolution. The simulation results show that there is a trade-off for frequency spacing parameter to have a good radar performance. Set the space too wide would destroy radar's speed resolution and too narrow would ruin its range resolution.