This letter proposes a new orthogonal frequency division multiplexing (OFDM)-based waveform, called time spread-windowed OFDM (TS-W-OFDM). TS-W-OFDM applies a windowing procedure to improve spectral efficiency and a time spreading method to create a block signal structure. Numerical results show that TS-W-OFDM has higher spectral efficiency and nearly same error rate compared to the conventional cyclic prefix-OFDM, windowed-OFDM (W-OFDM), weighted overlap and add-based OFDM (WOLA-OFDM), and filtered-OFDM (F-OFDM). In addition, they also show that TS-W-OFDM has lower complexity than W-OFDM, WOLA-OFDM, and F-OFDM.