Globally, hepatocellular carcinoma (HCC) ranks high among cancer-related deaths. In order to effectively manage HCC in the clinic, a variety of imaging modalities are necessary. Early detection, differentiation, precise staging, and evaluation of local, residual, and recurrent HCC have all been greatly enhanced by the introduction of positron-emission tomography (PET) or PET-computed tomography to the oncologic context. PET imaging provides a visual representation of treatment-related tissue metabolic data. Recent years have seen the rise of dual-tracer and dynamic PET imaging as supplementary tools for the diagnosis of HCC. Imaging techniques like immuno-PET and PET-magnetic resonance imaging, as well as novel radiotracers, have greatly enhanced lesion detection and therapy monitoring. Here we take a look back at what PET can provide for HCC diagnostics right now, as well as some supporting methods. Although 18F-FDG PET-CT has emerged as an important noninvasive diagnostic tool in HCC, especially in staging and detecting metastatic lesions, the low sensitivity of 18F-FDG PET-CT limits its clinical use, especially for routine surveillance. 18F-FDG PET-CT could be valuable in HCC staging and has a great impact on the clinical decision for HCC treatment