Embodiments of a master station and method for high-efficiency Wi-Fi (HEW) communication using a multi-device HEW preamble are generally described herein. In some embodiments, the master station may select a number of long-training fields (LTFs) to be included in the multi-device HEW preamble of an HEW frame. The HEW frame may comprise a plurality of links for transmission of a plurality of streams. The master station may transmit the selected number of LTFs sequentially as part of the HEW preamble and transmit a plurality of data fields to scheduled stations during an HEW control period. Each data field may correspond to one of the links and may comprise one or more streams. The selection of the number of LTFs to be included in the HEW preamble may be based on a maximum number of streams to be transmitted on a single link.