This depends on whether you are paying a salary from your own company.
Already paying a salary: unless you want to be paid at basic rate of tax (e.g. tax being deducted on the full pay at 20%) then it is advisable to stop paying your wage from the company. There is no tax benefit in keeping both wages active and you will pay more tax during the year.
In order to ensure your personal allowance is transferred to your employment, your employment should be stopped and when completing a P46 for your new employee, it should be stated that you do not have any other jobs.
Not paying a salary: there is nothing you should need to do, but ensure you are being taxed at the correct rate from your new employer.
You should also review the level of dividend payments you receive during the year. If your new salary is much higher than the wages declared through the company then the level of dividend, before tax is liable, will be reduced.
Consult your accountant as to how best to handle your new earnings structure to ensure tax efficiency all round.