您可以这样访问属性值：from elementtree.ElementTree import XML, SubElement, Element, tostring

text = """

"""

elem = XML(text)

for node in elem.find('phoneNumbers'):

print node.attrib['topic']

# Create sub elements

if node.attrib['topic']=="sys/phoneNumber/1":

tag = SubElement(node,'TagName')

tag.attrib['attr'] = 'AttribValue'

print tostring(elem)

忘了说，如果ElementTree版本大于1.3，可以使用XPath：elem.find('.//number[@topic="sys/phoneNumber/1"]')

或者你可以用这个简单的：for node in elem.findall('.//number'):

if node.attrib['topic']=="sys/phoneNumber/1":

tag = SubElement(node,'TagName')

tag.attrib['attr'] = 'AttribValue'