Some demonstrative embodiments of the invention include a method device and/or system of secure communication in a wireless network using a spatial division multiple access transmission scheme. The method, according to some demonstrative embodiments may include generating a set of N spatial channels to be transmitted, using a set of N respective antennas, to a set of K destination stations, by applying at least one precoding matrix to a set of inputs including K transmissions intended to the K destination stations, respectively, and one or more dither sequences, wherein the precoding matrix includes K beamforming vectors based on channel state information of the K stations, respectively, and one or more additional vectors orthogonal to the beamforming vectors. Other embodiments are described and claimed.