一种非常简单的方法：假设您希望导入具有相对路径../..的文件/MyLibs/pyfunc.py

libPath = '../../MyLibs'
import sys
if not libPath in sys.path: sys.path.append(libPath)
import pyfunc as pf

但如果你在没有守卫的情况下成功，你最终会走上一条很长的路。

有一个包专门针对这一点：

from thesmuggler import smuggle

# À la `import weapons`
weapons = smuggle('weapons.py')

# À la `from contraband import drugs, alcohol`
drugs, alcohol = smuggle('drugs', 'alcohol', source='contraband.py')

# À la `from contraband import drugs as dope, alcohol as booze`
dope, booze = smuggle('drugs', 'alcohol', source='contraband.py')

它在Python版本（Jython和PyPy也是）中进行了测试，但根据项目的大小，它可能会被过度使用。

这个答案是对Sebastian Rittau对评论的回答的补充：“但是如果你没有模块名怎么办？”这是一种快速而肮脏的方法，可以将可能的Python模块名指定为文件名——它只是沿着树向上移动，直到找到一个没有__init__.py文件的目录，然后将其转换回文件名。对于Python 3.4+（使用pathlib），这是有意义的，因为Python 2可以使用“imp”或其他方式进行相对导入：

import pathlib

def likely_python_module(filename):
    '''
    Given a filename or Path, return the "likely" python module name.  That is, iterate
    the parent directories until it doesn't contain an __init__.py file.

    :rtype: str
    '''
    p = pathlib.Path(filename).resolve()
    paths = []
    if p.name != '__init__.py':
        paths.append(p.stem)
    while True:
        p = p.parent
        if not p:
            break
        if not p.is_dir():
            break

        inits = [f for f in p.iterdir() if f.name == '__init__.py']
        if not inits:
            break

        paths.append(p.stem)

    return '.'.join(reversed(paths))

当然有改进的可能性，可选的__init__.py文件可能需要进行其他更改，但如果您通常有__init__.pry，这就有了窍门。

在运行时导入包模块（Python配方）

http://code.activestate.com/recipes/223972/

###################
##                #
## classloader.py #
##                #
###################

import sys, types

def _get_mod(modulePath):
    try:
        aMod = sys.modules[modulePath]
        if not isinstance(aMod, types.ModuleType):
            raise KeyError
    except KeyError:
        # The last [''] is very important!
        aMod = __import__(modulePath, globals(), locals(), [''])
        sys.modules[modulePath] = aMod
    return aMod

def _get_func(fullFuncName):
    """Retrieve a function object from a full dotted-package name."""

    # Parse out the path, module, and function
    lastDot = fullFuncName.rfind(u".")
    funcName = fullFuncName[lastDot + 1:]
    modPath = fullFuncName[:lastDot]

    aMod = _get_mod(modPath)
    aFunc = getattr(aMod, funcName)

    # Assert that the function is a *callable* attribute.
    assert callable(aFunc), u"%s is not callable." % fullFuncName

    # Return a reference to the function itself,
    # not the results of the function.
    return aFunc

def _get_class(fullClassName, parentClass=None):
    """Load a module and retrieve a class (NOT an instance).

    If the parentClass is supplied, className must be of parentClass
    or a subclass of parentClass (or None is returned).
    """
    aClass = _get_func(fullClassName)

    # Assert that the class is a subclass of parentClass.
    if parentClass is not None:
        if not issubclass(aClass, parentClass):
            raise TypeError(u"%s is not a subclass of %s" %
                            (fullClassName, parentClass))

    # Return a reference to the class itself, not an instantiated object.
    return aClass


######################
##       Usage      ##
######################

class StorageManager: pass
class StorageManagerMySQL(StorageManager): pass

def storage_object(aFullClassName, allOptions={}):
    aStoreClass = _get_class(aFullClassName, StorageManager)
    return aStoreClass(allOptions)

可以使用__import__和chdir执行此操作：

def import_file(full_path_to_module):
    try:
        import os
        module_dir, module_file = os.path.split(full_path_to_module)
        module_name, module_ext = os.path.splitext(module_file)
        save_cwd = os.getcwd()
        os.chdir(module_dir)
        module_obj = __import__(module_name)
        module_obj.__file__ = full_path_to_module
        globals()[module_name] = module_obj
        os.chdir(save_cwd)
    except Exception as e:
        raise ImportError(e)
    return module_obj


import_file('/home/somebody/somemodule.py')

这将允许在3.4中导入编译的（pyd）Python模块：

import sys
import importlib.machinery

def load_module(name, filename):
    # If the Loader finds the module name in this list it will use
    # module_name.__file__ instead so we need to delete it here
    if name in sys.modules:
        del sys.modules[name]
    loader = importlib.machinery.ExtensionFileLoader(name, filename)
    module = loader.load_module()
    locals()[name] = module
    globals()[name] = module

load_module('something', r'C:\Path\To\something.pyd')
something.do_something()