I can get object in S3 bucket when specifying region in ClientConfiguration: ClientConfiguration config; config.scheme = Scheme::HTTPS; config.connectTimeoutMs = 30000; config.requestTimeoutMs = 30000; config.region = Aws::Region::US_WEST_2; Aws::S3::S3Client Client(config); And I'm wondering whether there is a way to get the same object in S3 bucket without specifying the region, similar to java sdk. Thanks again for the great help! Johnny