The village is situated on the northern edge of the French Vexin plateau, to the south-west of the Oise and next to the Eure (27) and the Val d'Oise (95).
The village can be accessed by road and by train (SNCF Paris St Lazare - Gisors)
The village is built around a principal axis made up of the streets Général Ménard, Grande rue and rue de Loconville. The streets take their names from local villages : rue de Boubiers, rue de Loconville, route de Chaumont... or the old quarters : rue St Pierre, petite rue St Pierre, rue de la Rougette... or famous people : rue du général Ménard.
The village of Liancourt-Saint-Pierre includes four hamlets : Les Groux, Vaux, Launay and Le Vivray.
At the last census, taken in 2016 the population was 580 inhabitants.
Since the first records the number of inhabitants has always oscillated
between 400 and 650.