A 1.3 μm laser amplifier with integrated passive waveguides is demonstrated. The structure is easily integrable and is suitable for compensation of all kinds of losses in optoelectronic integrated circuits such as losses due to power splitting in switch matrices. A simple model is made to calculate the coupling efficiency and reflection between the active and passive waveguides of the amplifier. Experimental results are in agreement with the theoretical predictions. The highest obtained external cavity gain of the whole structure is 19.5 dB and the output power saturates at approximately 15 mW.