Cytogenetic studies were performed on Allium fistulosum, A. cepa. their F1 hybrid, and ten backcross (BC1) progenies [(A. fistulosum × A. cepa) × (A. cepa) 1. In meiosis the F1 hybrid showed 41 percent hetercmorphic bivalent pairing with 10.6 +. 1.8 `chiasmata per cell. Meiocytes were observed with one, two and three bridges and fragments, indicating at least three paracentric inversions. Multivalent associations indicate at least two translocations, one involving the satellite chromosome. The percentage of bivalent pairing, bridges and fragments, and multivalent associations varied in BC1 progenies. The F1 hybrid and all of the BC1 plants were either sterile or had very little seed set. The satellite chromosomes used as cytological markers showed variation in nucleolus position, degree of attachment and number.