The symbiotic FM radio data sys-tem (SRDS) is a radio data system that a spe-cially designed OFDM signal co-lives with FM signal, which enables a significantly high-er data rate than existing radio data systems. The cyclic prefix of the OFDM symbol has the same length as the OFDM body, which en-ables the analytic separation of the co-channel OFDM and FM signal at receiver side, utiliz-ing the fact that the OFDM body and prefix is equal. In this work, we show that the OFDM body and prefix cannot be viewed as equal when there is sufficient carrier frequency off-set (CFO). Thus, we propose a two-step CFO estimation algorithm for FM and SRDS hy-brid signal. The first step estimates the coarse CFO by exploring the characteristics of the FM signal. Once the coarse CFO is removed, the residual CFO is small enough for FM and OFDM separation. The second step fine esti-mates CFO from the OFDM-only signal using its repeated PN structure after the separation. Detailed mathematical equations are formu-lated and simulation results are given. The re-sults show that the proposed algorithm works fine with the simulation setup and has a final residual CFO less than 3.9Hz.