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Comprehensive Summary: β‐Amino acids (AAs), homologs of α‐AAs, are important building blocks of biological materials. Herein, chiral recognitions of β‐AAs with Ir(III) complexes are reported, in favor of formation of the thermodynamically stable Λ‐[Ir(pq)2(D‐β‐AAs)] and Δ‐[Ir(pq)2(L‐β‐AAs)] (pq is 2‐phenylquinoline) diastereomers. The photoreactions of [Ir(pq)2(β‐AA)] complexes are observed in an EtOH solution in the presence of O2 at room temperature. The primary β‐AAs complexes, such as rac‐[Ir(pq)2(β‐ala)] (β‐ala is β‐alanine), Δ‐[Ir(pq)2(D‐β‐ma)] and Λ‐[Ir(pq)2(D‐β‐ma)] (β‐ma is β‐methylalanine), Δ‐[Ir(pq)2(D‐β‐pa)] and Λ‐[Ir(pq)2(D‐β‐pa)] (β‐pa is β‐phenylalanine), and rac‐[Ir(pq)2(β‐dma)] (β‐dma is 3,3‐dimethyl‐β‐alanine), are interligand C—N cross‐coupling in situ between pq and β‐AAs ligands. The secondary β‐AA complexes Δ‐[Ir(pq)2(L‐β‐pro)] and Λ‐[Ir(pq)2(L‐β‐pro)] (β‐pro is β‐proline, 2‐(pyrrolidin‐2‐yl)acetic acid) are dehydrogenatively oxidized into imino acid complexes Δ‐[Ir(pq)2(L‐β‐pro‐2Hβ')] and Λ‐[Ir(pq)2(L‐β‐pro‐2Hβ')] (L‐β‐pro‐2Hβ' = 2‐(3,4‐dihydro‐ 2H‐pyrrol‐2‐yl)acetic acid), respectively. Moreover, the dehydrogenative reaction in Δ‐[Ir(pq)2(L‐β‐pro)] diastereomer is regioselective depending on the reaction temperature, affording Δ‐[Ir(pq)2(L‐β‐pro‐2Hβ')] and Δ‐[Ir(pq)2(L‐β‐pro‐2Hβ)] (β‐pro‐2Hβ = 2‐(3,4‐dihydro‐ 2H‐pyrrol‐5‐yl)acetic acid) at low temperature. The chiral recognitions and photoreactions of Ir(III)‐β‐AAs complexes are much different from the previous observations in Ir(III)‐α‐AAs complexes. [ABSTRACT FROM AUTHOR]