An efficient scheme of integer frequency offset estimate for orthogonal frequency division multiplexing (OFDM) systems is proposed based on a training symbol with several identical parts. In this scheme, the received training symbol is first reshaped into several sub-symbols. It shows that the reshaping process introduces time diversity multiplexing. After a special fast Fourier transform (FFT) algorithm is applied to the sub-symbol, the integer frequency is estimated by finding the maximum magnitude of the resulting frequency domain signal. To improve the estimate performance, diversity combining methods are presented to make full use of the multiple frequency domain sub-symbols. Compared to the traditional scheme, the proposed one has an improved estimate performance demonstrated by the computation simulation, while maintaining a very low complexity.