Entering from the narthex into the central part of the church, the monumental appearance of the church interior is overwhelming. All the walls and vaults are covered with frescoes. There are sixteen great cycles in the naos, and a large number of images of saints depicted in the form of standing figures.
On the front sides of the wide pillars on the right and left sides are frescoes of Christ and the Theotokos (the Holy Virgin). Christ is depicted with a sword in His hand, which is rare indeed, a sword that is the cutting blade for sin, while the Theotokos is once again a supplicant before Christ, first of all for the founder and benefactor of Dečani Monastery, whose tomb lies nearby, but also for every pilgrim who enters the church.

The marble tomb of Saint Stefan of Dečani is located in the western part of the south nave next to the chapel of Saint Nicholas and above the place where the King’s mortal remains rested until his glorification in 1343. The marble tomb to the left is similar to the King’s but is lower and smaller. According to the tradition St. Jelena Srpska (Saint Helen of Serbia), the sister of Holy King Stefan of Dečani, the latter Empress of Bulgaria who finally became a nun rests in it.