I have loged in to my apple iphone 5s with id previously i used but when i reset my iphone and i want to again sign in the mobile ask for the pascode previously i used to unlock iphone but i cant remember that one so i cant acess my data how shuld i

If you mean the phone is on the activation lock screen and you've forgotten the password for the account that it's locked to : http://iforgot.apple.com

Or : Contact Apple for help with Apple ID account security

Or, and if you were the original purchaser of the phone (i.e. it wasn’t bought used), you could try going to an Apple Store (make a Genius Bar appointment if you do) or try contacting iTunes Support online (https://www.apple.com/emea/support/itunes/contact.html) and see if they can remove the phone from the account - they are likely to want to see proof of ownership before they might help e.g. original receipt with the serial number on it

Are you asking about the Apple ID password or the passcode for the phone?

Passcode - If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled