In most cases yes, but not always.  In some occasions, an inversion occurs where the temperature actually increases as you go higher.  When a warmer, less dense air mass moves over a colder air mass this inversion occurs.  This is often associated with oceanic upwelling and warm fronts.

Also, the temperature profile in the atmosphere is that temperatures decrease with height in the troposphere and mesosphere, but temperatures increase with height in the stratosphere and the thermosphere.