The invention relates to an intelligent solar street lamp with a flexible structure and an automatic cleaning function. The intelligent solar street lamp comprises a base, a lamp pole, a lamp tube, asolar plate, a switching mechanism, a dust prevention mechanism and a washing mechanism, wherein the switching mechanism comprises a sliding ring, a sliding way, a fixed plate, a driving component andtwo switching rods; the dust prevention mechanism comprises a support plate, a horizontal movement component and two dust prevention components; each dust prevention component comprises a telescopicframe, a sleeve ring, a fixed rod, a lifting block and a dust prevention unit; each dust prevention unit comprises a cross rod, a first motor, an eccentric wheel, a support plate, a propping plate andtwo springs. According to the intelligent solar street lamp with the flexible structure and the automatic cleaning function, the switching mechanism is used for flexibly adjusting angles between thesolar plate and the lamp tube according to the current time; through cooperation of the lower dust prevention mechanism during operating, the dust prevention protection is achieved; meanwhile, the surface of the solar plate and the surface of the lamp tube can also be cleaned; through circulating in this way, the daytime photovoltaic power generation efficiency and the night lighting luminance areensured, so that the practicability of the intelligent solar street lamp is greatly improved.