Biological soil crusts are a universal and common feature of arid and semi-arid regions worldwide, and they greatly affect soil surface properties which may alter seed dispersal, germination and establishment of vascular plants. Few studies have examined the effects of biological soil crusts on vascular plants, and conclusions from these have been variable. In this study, we investigated the effects of two types of biological soil crusts (moss crust and algae crust) of five different ages on seed germination of two vascular plants, and the effects of crust condition (living crust and dead crust) on seed germination of three vascular plants. Biological soil crusts 18, 24, 41 and 49 years old from areas where the vegetation had been replanted were compared with 100 years old crusts from an area of natural vegetation. The presence of both algae and moss crusts significantly enhanced the germination of Bassia dasyphylla and Artemisia ordosica compared with surfaces from which the crusts had been removed. For both Bassia dasyphylla and Artemisia ordosica, there was no significant effect of crust age on germination on either moss crust or algae crust. The effects of crust type and crust condition on seed germination were variable and species-specific. Crust type significantly influenced germination of Bassia dasyphylla but not Artemisia ordosica and Eragrostis poaeoides. Living algae crust significantly increased germination of Artemisia ordosica, Eragrostis poaeoides and Bassia dasyphylla compared with dead crusts and uncrusted soil, while living moss crust enhanced the germination of both Artemisia ordosica and Bassia dasyphylla but not Eragrostis poaeoides. Our study indicates that biological soil crusts can have marked effects on the germination of some plant species.