  We investigate the Andreev reflection in the parallel double-quantum-dot
structure, by considering one metallic lead and one $s$-wave superconductor to
couple to the quantum dots simultaneously. It is found that the Fano lineshhape
has opportunities to appear in the linear conductance spectrum of the Andreev
reflection, which can be reversed by tuning the dot level or local magnetic
flux. However, the property of the Fano effect is very complicated, in
comparison with the normal electron tunnelling case. This is manifested as the
special Fano form of the linear-conductance expression and the interference
manner among the Feynman paths. We believe that this work can be helpful for
understanding the Fano interference in the Andreev reflection process.
