Low-pressure mercury vapour discharge lamp is provided with a discharge vessel (10) and a first and a second end portion (12a; 12b). The discharge vessel (10) encloses a discharge space (13) provided with a filling of mercury and a rare gas in a gastight manner. Each end portion (12a; 12b) supports an electrode (20a; 20b) which is arranged in the discharge space (13). Current supply conductors (30a, 30a′; 30b, 30b′) extend from the electrodes (20a; 20b) through the end portions (12a; 12b) to outside the discharge vessel (10). A UV-reflecting shield (15a; 15b) is positioned in the space between the electrodes (20a; 20b) and the end portions (12a; 12b), thereby protecting the end portions (12a; 12b) from the creation of reactive sites in the end portions (12a; 12b) at which reactive sites mercury is bound. Preferably, the shield (15a; 15b) is attached to the current supply conductors (30a, 30a′; 30b, 30b′). The lamp according to the invention has a comparatively low mercury consumption.