By default, Python regular expression split is case-sensitive. However, you can make it case-insensitive by using the re.IGNORECASE flag. For example: text = "apple,Apple,aPpLe" splits = re.split(r"apple", text, flags=re.IGNORECASE) print(splits) The output will be: ['', ',', ',', ''] In this case, the regular expression split matches the word "apple" regardless of its case.