This sounds like you have TimeZone support switched on perhaps on your iPhone and then your computer is on a different one.
TimeZone support is meant to automatically change meetings to the timezone you want so you don't have to keep working out the time difference say from east to west coast.
To check on the iPhone go to Settings, Mail,Contacts Calendars and then scroll down to see Time Zone Support. This should tell you were your iPhone is currently set to.