Should I train my employees on how to give a professional business presentation or should they be qualified to do this before being hired?

Yes of course, training is required your employees in order to give a professional business presentation. Because, in the matter of company’s expectations, template designs, contents, etc. employers knows better than employees and moreover how company is going to present business associates. Even if they are qualified in preparing powerful business presentation, it might be different scenario in your case comparing to your company role.

Yes I do agree that employees should qualified to do business presentations. Company can’t teach them like a training institute! At the best, companies may provide some awareness sessions about new features or knowledge about latest versions. Employees may join a professional course & be certified in order to consider them as qualified. 

First of all, you need to teach a person and become an example for him. And then your employees will be equal to you and work productively. Because if you want to do something, do it yourself. That is, teach people by their example.

No matter how professional you are, you have to follow organizational policy and rules and regulations. For that, you have to train your employees. Because every organization has own standards. Like writing letter in standard font format, font size, type, font color, letter pattern etc. Even logo size also matters logo color as well. So you have to educate your employee first.  

Absolutely,When you bring an employee on board , I am sure there is a certain amount of career planning being done and grooming them to make a Presentation should undoubtedly be an integral part..

At the end of the day , a knowledgeable employ would be a great asset to the organisation than one found wanting.

On the one hand, for all employees or newcomers It shouldn't, but it would be better. On other hand for some professions it is a must.

Thanks for invitation,

As a matter of fact "Presentation skills" is one of the most important "Soft Skills", which I believe that all staff has to be familiar with, despite of they have its training course for it, before or after hiring them. 

it depends on ur situation 

if you need someone will directly communicate with clients of customers you have to hire someone has this skill

On the other side if u hired some one not have this skill he/she maybe notable to learn this skill or has to work a lot for him/her

Depends on the role.  This is just one skill: if the role demands a lot of this, then of course they should have it.   But when you hire somebody you hire the whole person, and a whole person has a lot of skills and a lot of capacity to learn more skills.

Well there is scope improvement in every aspect and actions of a human being , If they know that skills give them advance level of training , if they are novice in presentation skills support them with beginner training.

If the desired profile / job required business presentations skill as a compulsory key skill , ensure to hire qualified person.  

Would be nice if they are trained beforehand, but then why limit yourself as you may have elements to add that prior work would not have given. Also something about tailoring training to your needs.