We reviewed the current status and future prospects of red broad area laser diodes (BA-LDs) and emphasized their output power and wall plug efficiency (WPE). As a countermeasure to catastrophic optical damage (COD),which limits lifetimes, 4.0 W CW operation is expected under a condition where the lifetime exceeds 20000 hours. A WPE of 40% was also achieved. The optical gain of the 660-nm-band LD, which is suitable for artificial plant cultivation, was close to that of the 638-nm LD. Therefore, the output power and the efficiency of 660-nm-band LDs are also expected to improve in the future as 638- nm LDs.