Flask-Admin and CKEditor WYSIWYG textarea integration. Basically, all you have to do: 1. Create new wtforms widget which will emit 'ckeditor' class 2. Make new wtforms field which will use this widget 3. Create new jinja2 template, which includes ckeditor javascript 4. Tell flask-admin to use new field and new template

ckedit.py

from flask import Flask
from flask.ext.sqlalchemy import SQLAlchemy

from flask.ext import admin, wtf
from flask.ext.admin.contrib import sqlamodel

app = Flask(__name__)
app.config['SECRET_KEY'] = '123456790'
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///test.sqlite'
db = SQLAlchemy(app)


class CKTextAreaWidget(wtf.TextArea):
    def __call__(self, field, **kwargs):
        kwargs.setdefault('class_', 'ckeditor')
        return super(CKTextAreaWidget, self).__call__(field, **kwargs)


class CKTextAreaField(wtf.TextAreaField):
    widget = CKTextAreaWidget()


class Test(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    text = db.Column(db.UnicodeText)


class TestAdmin(sqlamodel.ModelView):
    form_overrides = dict(text=CKTextAreaField)

    create_template = 'edit.html'
    edit_template = 'edit.html'


if __name__ == '__main__':
    admin = admin.Admin(app)
    admin.add_view(TestAdmin(Test, db.session))
    db.create_all()
    app.debug = True
    app.run('0.0.0.0', 8000)

edit.html

{% extends 'admin/model/edit.html' %}

{% block tail %}
    {{ super() }}
    <script src="http://cdnjs.cloudflare.com/ajax/libs/ckeditor/4.0.1/ckeditor.js"></script>
{% endblock %}

Check this answer for the simpler solution based on Flask-CKEditor.