Is it ok to join the police force if i have asthma ?

I don't see why not: I have a policewoman and fireman under my care who both have asthma. They are well-controlled so i think that helps. You should check to see if your local police have no restrictions on joining if you have asthma and then make sure your asthma is well-controlled and that your lung function is stable with an evaluation by either an allergy/asthma or pulmonary specialist.

Yes: At any time, up to 20-25% of the us olympic team has asthma. If having asthma does not prevent you from being a top athlete, it definitely should not prevent you from joining the police force.

Usually: Each agency can set standards of what they will accept based on their work environment, but as long as you are properly managed and can do strenuous exercise without more than rare need for your rescue inhaler, then should not be a problem.