Negative electrode and aluminum air cell

A negative electrode comprising an aluminum alloy,

• wherein the alloy has a magnesium content of 0.0001% by weight or higher and 8% by weight or lower,
• the alloy comprises an intermetallic compound particle in a matrix of the alloy,
• in a surface of the alloy, a particle-number density of the intermetallic compound particle having a particle size of 0.1 μm2 or larger and smaller than 100 μm2 is 1000 particles/mm2 or less,
• a particle-number density of the intermetallic compound particle having a particle size of 100 μm2 or larger is 10 particles/mm2 or less,
• an occupying area proportion of the intermetallic compound particle is 0.5% or smaller per unit area of the alloy surface,
• the alloy satisfies at least one condition selected from the group consisting of the following (A) and (B):
• (A) an iron content is 0.0001% to 0.005% by weight, and
• (B) a silicon content is 0.0001% by weight or higher and 0.02% by weight or lower, and
• a content of each element other than aluminum, magnesium, silicon and iron in the alloy is 0.005% by weight or lower.