An organic light emitting device and a manufacturing method thereof are provided. The organic light emitting device includes a first display substrate, a second display substrate, and a first adhesive force improving member. The first display substrate includes a first substrate, a first electrode, organic light emitting patterns, a first spacer, and a second electrode. The first electrode is formed on an entire surface of the first substrate, and the organic light emitting patterns are disposed on the first electrode. The first spacer corresponds to the organic light emitting pattern and is disposed on the first electrode. The second electrode covers the organic light emitting patterns and the first spacer. The second display substrate includes a second substrate, and a first driving signal delivery part. The first adhesive force improving member electrically/physically couples the second electrode to the first driving signal delivery part.