Abstract: The current study investigated spiders fauna and abundance of olive orchards in Guilan, Ghazvin, Golestan, Mazandaran and Zanjan provinces during 2002-2003. Valid spider keys identification used for species determination. Four speices Frontinellina fruntetorum (C.L. Koch, 1981) (Linyphidae), Thyene imperialis (Rossi,1846), Salticus scenicus (Clerk, 1757) (Salticidae) and Thomisus onustus, Walkenaer, 1806 (Thomisidae) of spider of the collection determined as dominant species. Uniform distribution and dominant spider species only recorded for F. fruntetorum in all provinces. Spiders abundance researchs at three olive orchards in Guilan, Ghazvin and Zanjan provinces. Population abundance of spider recorded by stroking to 8 olive branches of 30 trees at 15 days interval wicth onset from May to October. Among collected natural enemies fauna insects and spiders fauna 42.8% was belong to spider specimens and their population flactuation was varied from 25.4 to 60.7% in month of May to October, respectively.