This study was carried out in order to determine the bio-ecology of harmful corn leafhopper, Zyginidia sohrab Zatchvakin (Hemiptera: Cicadellidae) on maize plant in Diyarbakir province in the years of 2010 and 2012. For this purpose, its first emergence time to the nature, alternative host plants, population development in main and second crop maize and the number of generations per year were determined. The studies were done weekly from March to December at the maize cultivated areas and non agriculture land. It was found that Z. sohrab was came out at the earliest in the middle of April to nature, fed on narrow leaf weeds, especially the most preferred as weed was Sorghum halepense (L.) Pers. (Johnson grass), and passed to the main crop maize in the beginning of June. The population of Z. sohrab reached to peak level at the maturity stage on main crop maize, after the harvest, the population of Z. sohrab passed to the second crop maize and reached also to a peak level at the generative and maturity stage on the second crop maize was determined. The mean number of Z. sohrab adults detected on the yellow sticky traps at the second crop maize were eight time more than the main crop maize and it was also determined that the rate of population Z. sohrab became only dominated species by increasing over 90% among the other leafhopper species (E. decipiens and A. decedens, P. striatus) feeding on the maize plant. Besides it was determined that Z. sohrab gave five generations per year and entered to diapause period as adult depending on temperature in December. It was concluded that effective control against the weeds increasing density of the pest should be performed and except for chemical control, alternative control methods and biological control must be conducted on Z.sohrab.