Beaucroissant is located some 32 km south by south-east of
Bourgoin-Jallieu and 25 km north-west of
Grenoble. Access to the commune is by the D1085 road from
La Frette in the north-west which passes through the commune just north of the village and continues east to
Moirans. The D519 comes from
Izeaux in the west and passes through the commune turning north to join the
A48 autoroute at Exit . A railway from
Le Grand-Lemps passes through the commune with a station in the village and continues north-east to
Rives. Apart from the village there is the hamlet of Le Mollard. Apart from the large urban area of the village and Le Mollard the commune is mainly farmland. ==Toponymy==