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Chlorophyll breakdown is a vital catabolic process of leaf senescence as it allows the recycling of nitrogen and other nutrients. In the present study, we isolated rice senescence-induced receptor-like kinase (<i>OsSRLK</i>), whose transcription was upregulated in senescing rice leaves. The detached leaves of <i>ossrlk</i> mutant (<i>ossrlk</i>) contained more green pigment than those of the wild type (WT) during dark-induced senescence (DIS). HPLC and immunoblot assay revealed that degradation of chlorophyll and photosystem II proteins was repressed in <i>ossrlk</i> during DIS. Furthermore, ultrastructural analysis revealed that <i>ossrlk</i> leaves maintained the chloroplast structure with intact grana stacks during dark incubation; however, the retained green color and preserved chloroplast structures of <i>ossrlk</i> did not enhance the photosynthetic competence during age-dependent senescence in autumn. In <i>ossrlk</i>, the panicles per plant was increased and the spikelets per panicle were reduced, resulting in similar grain productivity between WT and <i>ossrlk</i>. By transcriptome analysis using RNA sequencing, genes related to phytohormone, senescence, and chlorophyll biogenesis were significantly altered in <i>ossrlk</i> compared to those in WT during DIS. Collectively, our findings indicate that <i>OsSRLK</i> may degrade chlorophyll by participating in a phytohormone-mediated pathway.