它很方便:

import os
import stat

size = 0
path_ = ""
def calculate(path=os.environ["SYSTEMROOT"]):
    global size, path_
    size = 0
    path_ = path

    for x, y, z in os.walk(path):
        for i in z:
            size += os.path.getsize(x + os.sep + i)

def cevir(x):
    global path_
    print(path_, x, "Byte")
    print(path_, x/1024, "Kilobyte")
    print(path_, x/1048576, "Megabyte")
    print(path_, x/1073741824, "Gigabyte")

calculate("C:\Users\Jundullah\Desktop")
cevir(size)

Output:
C:\Users\Jundullah\Desktop 87874712211 Byte
C:\Users\Jundullah\Desktop 85815148.64355469 Kilobyte
C:\Users\Jundullah\Desktop 83803.85609722137 Megabyte
C:\Users\Jundullah\Desktop 81.83970321994275 Gigabyte

要获取一个文件的大小，可以使用os.path.getsize()

>>> import os
>>> os.path.getsize("/path/file")
35L

它以字节为单位报告。

蒙纳特的答案是很好的，但它失败的符号链接，所以你还必须检查这个路径是否真的存在

if os.path.exists(fp):
    total_size += os.stat(fp).st_size

它很方便:

import os
import stat

size = 0
path_ = ""
def calculate(path=os.environ["SYSTEMROOT"]):
    global size, path_
    size = 0
    path_ = path

    for x, y, z in os.walk(path):
        for i in z:
            size += os.path.getsize(x + os.sep + i)

def cevir(x):
    global path_
    print(path_, x, "Byte")
    print(path_, x/1024, "Kilobyte")
    print(path_, x/1048576, "Megabyte")
    print(path_, x/1073741824, "Gigabyte")

calculate("C:\Users\Jundullah\Desktop")
cevir(size)

Output:
C:\Users\Jundullah\Desktop 87874712211 Byte
C:\Users\Jundullah\Desktop 85815148.64355469 Kilobyte
C:\Users\Jundullah\Desktop 83803.85609722137 Megabyte
C:\Users\Jundullah\Desktop 81.83970321994275 Gigabyte

我在这里有点晚(和新)，但我选择使用subprocess模块和Linux中的'du'命令行来检索文件夹大小的准确值，单位为MB。我必须使用if和elif用于根文件夹，否则子进程会由于返回的非零值而引发错误。

import subprocess
import os

#
# get folder size
#
def get_size(self, path):
    if os.path.exists(path) and path != '/':
        cmd = str(subprocess.check_output(['sudo', 'du', '-s', path])).\
            replace('b\'', '').replace('\'', '').split('\\t')[0]
        return float(cmd) / 1000000
    elif os.path.exists(path) and path == '/':
        cmd = str(subprocess.getoutput(['sudo du -s /'])). \
            replace('b\'', '').replace('\'', '').split('\n')
        val = cmd[len(cmd) - 1].replace('/', '').replace(' ', '')
        return float(val) / 1000000
    else: raise ValueError

Python 3.5使用os.scandir递归文件夹大小

def folder_size(path='.'):
    total = 0
    for entry in os.scandir(path):
        if entry.is_file():
            total += entry.stat().st_size
        elif entry.is_dir():
            total += folder_size(entry.path)
    return total