Objective: The primary objective of this study is to investigate the chemical composition, volatile components, and biological activity of pickled bamboo shoots in the Guangxi and Guangdong regions, as well as the regional characteristics and flavor formation mechanisms of these pickled bamboo shoots. Methods: Physical and chemical experiments were used to analyze the major components in fermented bamboo shoots and their extracts. The volatile flavor components in fermented bamboo shoots were identified and analyzed using headspace solid-phase microextraction gas chromatography-mass spectrometry （HS-SPME-GC-MS）. The antioxidant activity of fermented bamboo shoot extracts was evaluated using in vitro antioxidant activity methods （ABTS free radical scavenging method, DPPH free radical scavenging method, and FRAP method）. Results: There were no significant differences in moisture, pH, total soluble sugars, fats, amino acid nitrogen, and nitrite content between the pickled bamboo shoots from Guangxi Liuzhou Tianyi Agricultural Technology Co Ltd （hereinafter referred to as GXLZTY） and those from the Shaoguan Nanxiong Agricultural Trade Market in Northern Guangdong （hereinafter referred to as GDYBNX）. However, there were significant differences between the two in terms of chloride, total acids, proteins, dietary fibers, total flavonoids, total polyphenols, and mineral element content. Analysis of volatile components indicated that the main constituents in GXLZTY fermented bamboo shoots were P-cresol, hexanoic acid, octanoic acid, 2-ethylhexanol, and sulfur dioxide, while the primary components in fermented bamboo shoots from GDYBNX were p-cresol, acetic acid, and serinol. Antioxidant activity test results showed that the GXLZTY sour bamboo shoot extracts were superior in terms of clearing ABTS free radicals, DPPH free radicals, and FRAP activity compared to the extracts from GDYBNX. Conclusion: GXLZTY fermented bamboo shoots have higher nutritional value and antioxidant activity. These research results provide a theoretical basis for the fermentation process and industrial production of fermented bamboo shoots.