<p>Recently, miniature sensors have become an integral part of daily life to deliver intelligent services, such as smartphones, smartwatches, smart cars, <i>etc.</i> However, traditional physical sensing methods face limitations when it comes to detecting biochemical targets. To address this, biological and chemical sensing interfaces, constructed from a wide array of materials such as small molecule groups/probes, polymers, enzymes, antibodies, and nucleic acids, enable highly sensitive and selective recognition of specific targets. Microfluidic chip, portable monitoring instruments, clinical rapid diagnostic tools, and wearable or implantable devices based on these sensing interfaces have garnered significant attention. In this review, we focus on the critical components of miniature optical sensors, emphasizing their design principles, material selection, and integration strategies. We review the recent advancements in nanomaterials, reactive substrates, microfluidics, and miniature devices that aim to enhance sensor performance. Additionally, we highlight the significance of optical signal enhancement and efficient data processing techniques. By presenting a comprehensive approach to the design and optimization of optical sensing interfaces, this review seeks to provide insights into the development of more efficient and portable miniature optical sensors for various research applications.</p>