Long-term variations and periods of Mira stars from ROTSE–IIId

► Long-term variations and periods of Mira Stars from ROTSE–IIId. ► The periods, amplitudes and epochs of maximums of Mira stars. ► 17 periods of Mira variables are identified for the first time. ► The observations of Mira variables with ROTSE–IIId. We have studied the long-term variations of Mira type variables observed with Robotic Optical Transient Search Experiment telescope (ROTSE–IIId) between 2004 and 2009 located at TÜBİTAK National Observatory (TUG) in Antalya, Turkey. The actual pulsation periods, variability amplitudes, epochs of maximums and light curves of selected 70 Mira type variables already defined in the SIMBAD database were investigated. In these variables, 17 periods are identified for the first time.