Lipids play a crucial role in the development of metabolic diseases. However, traditional imaging techniques still face challenges such as low sensitivity and insufficient penetration depth in the specific imaging of lipid tissues. To improve lipid imaging capabilities and meet the needs of clinical translation, we develop a handheld multispectral photoacoustic imaging probe integrated with D?O coupling and multiwavelength excitation, enabling label-free and high-sensitivity lipid detection through non-negative matrix factorization-based spectral unmixing. Comparative experiments on oil sample in the tube, ex vivo adipose tissues, and pork belly phantom demonstrate that the signal-to-noise ratio of lipid images at 1210 nm improves by approximately 33 dB over 930 nm. Lipid signal intensities are 4.9?6.0 times that of the 930 nm band. In in vivo imaging of mouse abdominal fat, the system achieves a noninvasive imaging depth exceeding 1.5 cm, revealing clear and accurately localized lipid distributions in complex tissue environments. This work represents the implementation of D₂O coupling in a portable probe, substantially improving photoacoustic signal transmission efficiency at high-absorption near-infrared wavelengths. The system offers a lightweight and practical solution for lipid imaging, providing a novel technical pathway for early screening and clinical monitoring of lipid metabolism-related disorders.