Silicon photonics is a promising integrated-optics platform for optical communication and sensing applications. Integrating 2–3 μm wavelength widely tunable lasers on silicon photonic integrated circuits enables fully integrated spectroscopic sensors with different potential applications such as multi-species trace gas spectroscopy and bio-molecule detection. Here, we demonstrate a continuous-wave (CW) operated III–V-on-silicon distributed feedback (DFB) laser array covered a broad wavelength range from 2.28 to 2.43 μm. CW operation up to 25°C and an on-chip output power of 2.7 mW in a single mode at 5°C is achieved for lasers operating at 2.35 μm wavelength. Four-channel DFB laser arrays with a continuous tuning range of 10 nm and side mode suppression ratio of 40 dB over the whole range are also presented. This work is a major advance toward chip-scale silicon photonics spectroscopic sensing systems.