This paper proposes MM-Retinal-Reason, the first multimodal ophthalmology dataset capable of performing various types of inference (basic and complex) in the ophthalmology domain, and a multimodal inference model, OphthaReason, based on it. OphthaReason demonstrates a step-by-step inference process and flexibly adapts to both basic and complex inference tasks using the Uncertainty-Aware Dynamic Reasoning (UADT) technique. Experimental results show that OphthaReason achieves at least 15% performance improvement over existing models (general-purpose MLLM, medical MLLM, reinforcement learning-based medical MLLM, and ophthalmology MLLM).