| GEO-K | |
| GeoDataLab S.r.l.s. | |
| Geodesign | Como |
| Geodetica Volpe S.a.s. | Rome |
| GeoGraphics S.r.l. | Ferrara |
| GeoSolutions | Lucca |
| Gesan Production S.r.l. | |
| Gestione Albergo | Florence |
| Get Ready Computer | Pavia |
| Geva Elettronica | Turin |
| GEVI | |
| GGallery S.r.l. | Genoa |
| Gi Group Holding S.p.A. | |
| Giannone Computers S.a.s. | Ragusa |
| GiBiLogic S.r.l. | Brescia |
| GiDiNet.com | Rome |
| Giffoni Innovation Hub S.r.l. | |
| Gigasoftware.it | Catania |
| Gigaword S.n.c. | Bari |
| Giordano Designer | |
| Giuseppe Izzinosa | Turin |
| Givi Misure S.r.l. | |
| Gixo S.r.l. | Monza and Brianza |
| Glaut | |
| GlioGuard | |
| Global Display Solutions S.p.A. | |
| GlobalMente | Milan |
| GloboSpace.com | Salerno |
| GM Servizi S.r.l. | |
| Gmg Net S.r.l. | |
| GMSpazio S.r.l. | |
| Gnucoop Soc. Coop. | Milan |
| GNV & Partners S.r.l. | Rimini |
| Go Electric Stations S.r.l.s. | |
| GO internet S.p.A. | |
| GoalShouter S.r.l. | Milan |
| GoLab | Florence |
| Golden Eggs Agency | |
| Goldnet S.r.l. | Vicenza |
| Goma Elettronica S.p.A. | Turin |
| GOODGLYPH S.r.l. | |
| goplaceit S.p.A. | |
| Gotha Advisory S.p.A. | Milan |
| GoVolt S.r.l. | |
| GPS Green Power Solutions S.r.l. | Genoa |
| GR Sistemi Automatici di Apertura S.r.l. | Mantua |
| Graf S.p.A. | Modena |
| Graf.el S.r.l. | Milan |
| Graffio S.r.l. | |
| Graffiti | Rome |