1、新建一个run.py(要运行的文件)，代码如下

# -*- coding: utf-8 -*-
"""
文件名称:  run.py
文件创建时间:  2021/8/10 11:08
软件名称:   PyCharm
文件作者:  黄氏
"""
import sys

from PySide6 import QtCore
from PySide6.QtWidgets import QApplication
import pandas as mypd

# 导入所画的界面
from  tabledemo import *

# 自定义类
class Excel_Table(QMainWindow, Ui_MainWindow):
    def __init__(self):
        super().__init__()
        self.setupUi(self)

        self.excelButton.clicked.connect(self.Open_Excel_File) # connect作用就是执行某个函数
        self.saveButton.clicked.connect(self.Excel_Save)

    def Open_Excel_File(self):
        excel_name = QFileDialog.getOpenFileName(self, '选择文件', '', 'Excel files(*.xlsx)')   # 过滤出xlsx格式的文件
        self.path_excel_name = excel_name[0]
        print("Excel文档的路径： ", self.path_excel_name)
        if len(self.path_excel_name) > 0:
            self.Read_Excel_Data()
            self.Table_Initialize()

    # 读取 EXCEL 文档的数据
    def Read_Excel_Data(self):
        self.excel_file = mypd.read_excel(self.path_excel_name)
        # 获取数据的行标签与列标签
        self.columns = self.excel_file.columns
        self.rows = self.excel_file.index

    # 定义表格的初始化参数
    def Table_Initialize(self):
        self.tableWidget.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
        self.tableWidget.setRowCount(len(self.rows))    # 设置表格的行数
        self.tableWidget.setColumnCount(len(self.columns))  # 设置表格的列数
        self.tableWidget.setHorizontalHeaderLabels(self.columns) # 设置表格的列标签
        self.tableWidget.setGeometry(QtCore.QRect(223,120,1000,800)) # 重新设置表格区域的大小
        # 将 EXCEL 文档的数据显示在表格中
        for i in range(len(self.rows)):
            for j in range(len(self.columns)):
                tstr = str(self.excel_file.iloc[i][j])
                data = QTableWidgetItem(tstr)
                self.tableWidget.setItem(i, j, data)

        self.tableWidget.resizeColumnsToContents() # 列宽随着内容调整
        self.tableWidget.resizeRowsToContents() # 行宽随着内容调整
        self.tableWidget.setAlternatingRowColors(True)  # 表格的颜色交错显示
        self.tableWidget.itemChanged.connect(self.Table_Data_Change) # 将表格中单元格改变时，触发 Table_Data_Change 事件

    # 当表格的内容改变时获取内容
    def Table_Data_Change(self,item):
        text = item.text()
        itemrow = item.row()
        itemcol = item.column()
        self.excel_file.iloc[itemrow,itemcol] = text # 使用[i][j]形式会报销

def Excel_Save(self): self.excel_file.to_excel(self.path_excel_name, index=False) if __name__ == '__main__': app = QApplication(sys.argv) excelTable = Excel_Table() excelTable.show() sys.exit(app.exec())

2、新建一个ui的python文档，文件 tabledemo.py 代码如下(我是用QtDesigner设计，通过PyUIC命令转换过来的)

# -*- coding: utf-8 -*-

################################################################################
## Form generated from reading UI file 'tabledemo.ui'
##
## Created by: Qt User Interface Compiler version 6.1.2
##
## WARNING! All changes made in this file will be lost when recompiling UI file!
################################################################################

from PySide6.QtCore import *  # type: ignore
from PySide6.QtGui import *  # type: ignore
from PySide6.QtWidgets import *  # type: ignore


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        if not MainWindow.objectName():
            MainWindow.setObjectName(u"MainWindow")
        MainWindow.resize(918, 538)
        sizePolicy = QSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(MainWindow.sizePolicy().hasHeightForWidth())
        MainWindow.setSizePolicy(sizePolicy)
        MainWindow.setLayoutDirection(Qt.LeftToRight)
        self.centralwidget = QWidget(MainWindow)
        self.centralwidget.setObjectName(u"centralwidget")
        self.formLayout = QFormLayout(self.centralwidget)
        self.formLayout.setObjectName(u"formLayout")
        self.horizontalLayout = QHBoxLayout()
        self.horizontalLayout.setObjectName(u"horizontalLayout")
        self.excelButton = QPushButton(self.centralwidget)
        self.excelButton.setObjectName(u"excelButton")

        self.horizontalLayout.addWidget(self.excelButton)

        self.horizontalSpacer = QSpacerItem(808, 17, QSizePolicy.Expanding, QSizePolicy.Minimum)

        self.horizontalLayout.addItem(self.horizontalSpacer)


        self.formLayout.setLayout(0, QFormLayout.LabelRole, self.horizontalLayout)

        self.horizontalLayout_2 = QHBoxLayout()
        self.horizontalLayout_2.setObjectName(u"horizontalLayout_2")
        self.horizontalSpacer_2 = QSpacerItem(828, 18, QSizePolicy.Expanding, QSizePolicy.Minimum)

        self.horizontalLayout_2.addItem(self.horizontalSpacer_2)

        self.saveButton = QPushButton(self.centralwidget)
        self.saveButton.setObjectName(u"saveButton")
        sizePolicy1 = QSizePolicy(QSizePolicy.Fixed, QSizePolicy.Fixed)
        sizePolicy1.setHorizontalStretch(0)
        sizePolicy1.setVerticalStretch(0)
        sizePolicy1.setHeightForWidth(self.saveButton.sizePolicy().hasHeightForWidth())
        self.saveButton.setSizePolicy(sizePolicy1)
        self.saveButton.setContextMenuPolicy(Qt.DefaultContextMenu)
        self.saveButton.setLayoutDirection(Qt.LeftToRight)

        self.horizontalLayout_2.addWidget(self.saveButton)


        self.formLayout.setLayout(2, QFormLayout.LabelRole, self.horizontalLayout_2)

        self.tableWidget = QTableWidget(self.centralwidget)
        self.tableWidget.setObjectName(u"tableWidget")
        self.tableWidget.setSizeAdjustPolicy(QAbstractScrollArea.AdjustToContents)

        self.formLayout.setWidget(1, QFormLayout.SpanningRole, self.tableWidget)

        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QMenuBar(MainWindow)
        self.menubar.setObjectName(u"menubar")
        self.menubar.setGeometry(QRect(0, 0, 918, 22))
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QStatusBar(MainWindow)
        self.statusbar.setObjectName(u"statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)

        QMetaObject.connectSlotsByName(MainWindow)
    # setupUi

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(QCoreApplication.translate("MainWindow", u"MainWindow", None))
        self.excelButton.setText(QCoreApplication.translate("MainWindow", u"\u6253\u5f00Excel", None))
        self.saveButton.setText(QCoreApplication.translate("MainWindow", u"\u4fdd \u5b58", None))
    # retranslateUi