Heimweiler is an Ortsgemeinde – a municipality belonging to a Verbandsgemeinde, a kind of collective municipality – in the Bad Kreuznach district in Rhineland-Palatinate, Germany. It belongs to the Verbandsgemeinde Kirner Land, whose seat is in the town of Kirn.
Heimweiler lies at the edge of the North Palatine Uplands along Landesstraße 182 (Kirn–Meisenheim) and on Kreisstraße 71, which links the two centres of Heimberg and Krebsweiler together. The municipal area measures 9.07 km2, and the average elevation is 259 m above sea level.
Clockwise from the north, Heimweiler's neighbours are the municipalities of Meckenbach, Merxheim, Limbach, Becherbach bei Kirn, Schmidthachenbach and Bärenbach, and the town of Kirn. Schmidthachenbach lies in the neighbouring Birkenfeld district.
Heimweiler's Ortsteile are Heimberg and Krebsweiler. The municipality's name is thus a portmanteau of its constituent communities’ names. Also belonging to Heimweiler are the outlying homesteads of Forsthaus Krebsweiler, Obere Horbachsmühle and Untere Horbachsmühle.
The Ortsgemeinde of Heimweiler came into being in 1969 through the merger of the two formerly self-administering municipalities of Heimberg and Krebsweiler. Archaeological finds from the Early Roman cremation grave near Krebsweiler and the prehistoric barrow in Heimberg's outlying countryside show that there were early settlers within what are now both Heimweiler's constituent communities. Like most of the district's places, Heimberg's and Krebsweiler's foundings might have come about during the “opening up of the newer settlement area” (7th to 12th centuries). In 1375, both Krebsweiler and Heimberg had their first documentary mention as Krebeswilre and Heymberch. Both villages belonged until the late 18th century to the Amt of Naumburg. The two together formed an Ingericht (“in-court”) within the court district of Becherbach. This mediaeval jurisdictional and administrative body, which was coterminous with the parish of Becherbach, might well first have been subject to Raugravial administration, which beginning in the 14th century passed to the Counts of Sponheim-Kreuznach.