diff --git a/r/R/filesystem.R b/r/R/filesystem.R
index d6554239f630..5a1e0eab6066 100644
--- a/r/R/filesystem.R
+++ b/r/R/filesystem.R
@@ -167,8 +167,9 @@ FileSelector$create <- function(base_dir, allow_not_found = FALSE, recursive = F
 #'   with `expiration`
 #' - `expiration`: `POSIXct`. optional datetime representing point at which
 #'   `access_token` will expire.
-#' - `json_credentials`: optional string for authentication. Point to a JSON
-#'   credentials file downloaded from GCS.
+#' - `json_credentials`: optional string for authentication. Either a string
+#'   containing JSON credentials or a path to their location on the filesystem.
+#'   If a path to credentials is given, the file should be UTF-8 encoded.
 #' - `endpoint_override`: if non-empty, will connect to provided host name / port,
 #'   such as "localhost:9001", instead of default GCS ones. This is primarily useful
 #'   for testing purposes.
@@ -572,6 +573,11 @@ GcsFileSystem$create <- function(anonymous = FALSE, retry_limit_seconds = 15, ..
 
   options$retry_limit_seconds <- retry_limit_seconds
 
+  # Handle reading json_credentials from the filesystem
+  if ("json_credentials" %in% names(options) && file.exists(options[["json_credentials"]])) {
+    options[["json_credentials"]] <- paste(read_file_utf8(options[["json_credentials"]]), collapse = "\n")
+  }
+
   fs___GcsFileSystem__Make(anonymous, options)
 }
 
@@ -657,3 +663,10 @@ clean_path_rel <- function(path) {
   path_sep <- ifelse(tolower(Sys.info()[["sysname"]]) == "windows", "\\\\", "/")
   gsub(path_sep, "/", path)
 }
+
+read_file_utf8 <- function(file) {
+  res <- readBin(file, "raw", n = file.size(file))
+  res <- rawToChar(res)
+  Encoding(res) <- "UTF-8"
+  res
+}
diff --git a/r/man/FileSystem.Rd b/r/man/FileSystem.Rd
index c9586f70e716..38c694af995c 100644
--- a/r/man/FileSystem.Rd
+++ b/r/man/FileSystem.Rd
@@ -69,8 +69,9 @@ credentials using standard GCS configuration methods.
 with \code{expiration}
 \item \code{expiration}: \code{POSIXct}. optional datetime representing point at which
 \code{access_token} will expire.
-\item \code{json_credentials}: optional string for authentication. Point to a JSON
-credentials file downloaded from GCS.
+\item \code{json_credentials}: optional string for authentication. Either a string
+containing JSON credentials or a path to their location on the filesystem.
+If a path to credentials is given, the file should be UTF-8 encoded.
 \item \code{endpoint_override}: if non-empty, will connect to provided host name / port,
 such as "localhost:9001", instead of default GCS ones. This is primarily useful
 for testing purposes.
diff --git a/r/tests/testthat/test-gcs.R b/r/tests/testthat/test-gcs.R
index e284beb225e2..fd173e923b27 100644
--- a/r/tests/testthat/test-gcs.R
+++ b/r/tests/testthat/test-gcs.R
@@ -91,6 +91,30 @@ test_that("GcsFileSystem$create() input validation", {
   )
 })
 
+test_that("GcsFileSystem$create() can read json_credentials", {
+  # From string
+  fs <- GcsFileSystem$create(json_credentials = "fromstring")
+  expect_equal(fs$options$json_credentials, "fromstring")
+
+  # From disk
+  cred_string <- '{"key" : "valu\u00e9"}'
+  cred_string_bytes_utf8 <- iconv(
+    cred_string,
+    from = Encoding(cred_string),
+    to = "UTF-8",
+    toRaw = TRUE
+  )[[1]]
+
+  cred_path <- tempfile()
+  on.exit(unlink(cred_path))
+  con <- file(cred_path, open = "wb")
+  writeBin(cred_string_bytes_utf8, con)
+  close(con)
+
+  fs <- GcsFileSystem$create(json_credentials = cred_path)
+  expect_equal(fs$options$json_credentials, "{\"key\" : \"valué\"}")
+})
+
 skip_on_cran()
 skip_if_not(system('python -c "import testbench"') == 0, message = "googleapis-storage-testbench is not installed.")
 library(dplyr)