The Supreme Constitutional Court (SCC) Judge Anwar Al-Aasy said that: "Article 3 of the Law 202 for the year 2014 which regulates the individual seats system for the house of representatives is unconstitutional," Al Ahram online reported.
The ruling referred to sections of the law on division of electoral districts.
The petitioners against the constitutionality of Law 202 have argued that it violates Article 106 of the constitution, which stipulates equality among constituencies in terms of population density and number of voters.
Egypt has been without its main parliament chamber since 2012 when it was dissolved by a court ruling.
More From This Section
The elections are the final step of a transitional roadmap outlined by the military in July 2013 after the overthrow of President Mohammed Morsi.
The court also ordered the cabinet to pay an amount of Egyptian pounds 200 in attorney fees.
Meanwhile, the court rejected the lawsuits filed against the electoral law regulating the exercise of political rights issued in 2014.
Sisi approved a constituencies law in December creating 567 parliamentary seats, 420 of which would be contested by individual candidates, 120 allocated according to party lists and 27 assigned by the president.