Abstract: Meadow spittlebug, Philaenus spumarius (L.), has recently been a subject of interest to biologists due to various genetic factors. This species is widely distributed and has been reported to exist in different parts of the world. Dlabola reported the species for the first time from Iran. A number of studies have been done on substantial activities of this spittle bug on Alhaghi pseudalhagi (M. Bieb.) Desv. camel thorn plant from Fabaceae family in Mashhad region, Khorasan Razavi during 2005-2006. In weekly investigations, it was noted that the spittlebug begins its activity from early spring as first instars and produces froth after nourishing on camel thorn plant. The bug had 5 instar ages in total and they spend the whole first year of their lives in their self-produced foam. The adult spittle bug appeared in late May without any froth production activity however, they produced a thin liquid-like discharge. This spittlebug had 3 generations on the camel thorn plant among which, unlike the first generation instars, the 2nd and the 3rd instars had fully grown wings, were able to move freely on the plant and were resilient to some extent. The latter generations did not produce any froth and still had a very thin discharge which moisturized the total body of the plant as well as the ground around it. Density of the 2nd and the 3rd generations of spittle bugs were higher than the first generation. Those spittle bugs from the 3rd generation which managed to reach their adulthood, mated and after laying eggs, entered their hibernation period. According to our investigations, duration of one generation of the spittle bug in Mashhad region fluctuates from approximately 60-83 days in spring and 44-56 days in summer. The population of the bug reached its maximum in summer in 2006 and early summer in 2007. We found out that the bug, among all different species of camel thorn plant in natural growth areas, is only activating on few specific species of the plant.