Louise: How many times a day should a person urinate?
Dr. Dean: It is more important to pay attention to an abnormal color or concentration of urine than to frequency.
How often we urinate depends so much on changeable conditions like the temperature, our activity, and how much fluid we're getting that we usually can't accurately judge what is too frequent. Most of the time if we are urinating more than we usually do, it's because we are drinking a lot.
It is true, though, that frequent urination is a symptom of diabetes and of a couple of very rare conditions, so you should of course check with your doctor if you are concerned.