As bisacylphosphine oxides are highly efficient, cleavable photoinitiators for visible light curing, we were interested in preparing diacylgermane 2. The UV-vis absorption maximum of the n-pi* transition was red-shifted up to 50 nm. Photo-DSC results of 2 showed similar reactivity to bisacylphosphine oxides under broadband irradiation experiments. Irradiation with a dental LED lamp gave significantly improved initiation behavior compared to bisacylphosphine oxides and camphorquinone, especially in aqueous acidic primer formulations. Application-oriented tests in dental adhesive or composite formulations showed sufficient storage stability, high photocuring activity, excellent photobleaching behavior, and mechanical properties of the materials.