The utility model discloses a petroleum industrial wastewater treatment system comprising a pretreatment device, a multi-effect evaporation device and a condensation device, wherein the pretreatment device comprises a multi-medium filter and a microfilter; the multi-effect evaporation device comprises N evaporator groups, each evaporator group comprises M evaporators, and each evaporator is provided with an evaporator shell pass and an evaporator tube pass; and the condensation device is provided with a condensation tube pass and a condensation shell pass, wherein the condensation shell pass is provided with a condensation shell pass inlet end and a condensation shell pass outlet end, the condensation shell pass inlet end is communicated with a first condensation channel and a second condensation channel, the condensation shell pass outlet end is used for outputting fresh water, and a condensed liquid can be introduced to the condensation tube pass. Due to the adoption of the structure, salt-containing wastewater in petroleum industry is subjected to evaporation treatment, and meanwhile, the salt-containing wastewater is converted into fresh water, so that the wastewater can be recycled; and waste heat in petroleum industry is also sufficiently utilized, so that the energy consumption caused in the petrochemical industrial production process can also be reduced.