I can't switch on my IPHONE 5s with out charger?

I have IPhone 5s. I can't switch on my IPhone 5s even i push switch on button but when i plug in charger it become switch on automatically. How i switch on IPhone without charger?

Your iPhone 5s's battery is probably completely dead now and will no longer hold a charge. Time to get a new phone or try replacing the battery…

Try to replace the battery. If there's no effect, the other probably reason is that the flex cable is loose. Take it to the repair shop and fix it.