Zhejiang rosy vinegar (ZRV) fermentation is a complex, spontaneous open-system process, where microbial communities are key to its unique characteristics. However, the precise influence of the brewing workshop environment on these dynamic microbial communities remains underexplored, hindering consistent product quality. Here, we characterized the environmental and fermentation microbial communities across three factories using high-throughput sequencing (16S rRNA and ITS), qPCR, and advanced ecological network analyses. Our results establish that the brewing environment acts as a critical, heterogeneous, and factory-specific microbial reservoir, and provides the primary inoculum for fermentation initiation. Our findings revealed significant inter-factory differences in environmental microbial loads and community structures. For instance, the SX environment was characterized by a unique composition, including the notable presence of Monascus on jar lids. Source tracking confirmed this environmental "seeding" significantly shapes initial fermentation communities, with contributions from floor and jar surfaces. During fermentation, bacterial communities consistently shifted (LAB decrease, Acetobacter increase), but fungal successions varied notably by factory. Specifically, the natural fermentation at the SX factory fostered a distinct fungal community trajectory, characterized by a unique decrease in Saccharomyces and the emergence of Monascus as the dominant genus in later stages. This trajectory was directly linked to its distinct environmental fungal populations and their pronounced influence from the initial solid-state phase. While internal selective pressures eventually govern community structure, environmental conditions profoundly dictate overall microbial diversity and succession. A core microbiome (Bacillus, Sphingomonas, Cryptococcus, Monascus), consistently present in both environmental and fermentation niches, served as key microbial bridges. Our results provide a vital basis for optimizing ZRV production by strategically managing the environmental microbiome to enhance quality and consistency.