Auxin is an important phytohormone for plant growth and development, and PIN proteins are critical auxin efflux carriers. In Arabidopsis thaliana, PIN-FORMED1 (PIN1) functions in inflorescence and root development. In rice (Oryza sativa L.), there are four PIN1 homologs (OsPIN1a - 1d), but their functions remain largely unexplored. Here, we created rice pin1a, pin1b, pin1c, pin1d, pin1a pin1b, and pin1c pin1d mutants using CRISPR/Cas9 technology and used them to study the functions of the four OsPIN1 paralogs in rice. In wild-type rice, all four OsPIN1 genes were relatively highly expressed in the root compared to other tissues. Compared to the wild type, the OsPIN1 single mutants had no dramatic phenotypes, but the pin1a pin1b double mutant had shorter shoots and primary roots, fewer crown roots, reduced root gravitropic responsiveness, longer root hairs, and larger panicle branch angle. Furthermore, the pin1c pin1d double mutant showed no observable phenotype at the seedling stage, but showed naked, pin-shape inflorescences at flowering. These data suggest that OsPIN1a and OsPIN1b are involved in root, shoot and inflorescence development in rice, whereas OsPIN1c and OsPIN1d mainly function in panicle formation. Our study provides basic knowledge and materials for the study of auxin transport and signaling in rice.