Some demonstrative embodiments include apparatuses, systems and/or methods of setting transmit slots in a wireless communication network. For example, an apparatus may include a scheduler to set a suggested start time of a first transmit slot to transmit over a wireless communication medium, and, if a start of a medium free time for the wireless communication medium is after the suggested start time, to shift the suggested start time to a shifted start time that coincides with the start of the medium free time, and to set a suggested start time of a second transmit slot based on the shifted start time.