In this paper, analog-and-digital hybrid beamformer design is considered for millimeter-wave (mmWave) wideband multi-user (MU) multiple-input single-output (MISO)-OFDM downlink systems, where a single common analog beamformer is used for all subcarriers while a separate digital beamformer is applied to each subcarrier. By applying a signal-to-leakage-plus-noise ratio (SLNR) approach, an efficient beamformer design algorithm based on a trace quotient is derived for joint design of the common analog beamformer and the separate digital beamformers.