A laterally grown edge emitting laser is provided. A semiconductor structure is disposed on a substrate. A first, a second and a third III-V optical layers are sequentially and laterally grown on and from a sidewall of the semiconductor structure. A cladding semiconductor layer is disposed next to the third III-V optical layer and electrically connected to the III-V optical layer. Then, a first contact structure and a second contact structure is disposed on and electrically connected to the semiconductor structure and the cladding semiconductor layer, respectively. In the edge emitting laser, each of the first, second and third III-V optical layers may independently include a III-V semiconductor including at least one of group III elements of boron (B), gallium (Ga), aluminum (Al) and indium (In), and at least one of group V elements of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb) and bismuth (Bi). The laterally grown edge emitting laser may be integrated with a metal-oxide-semiconductor field-effect transistor (MOSFET). A method for manufacturing the laterally grown edge emitting laser is also provided.