Liver cancer is the sixth most common cause of cancer death in Australia. Hepatocellular carcinoma (HCC) is the most prevalent type of primary liver cancer. Obesity and diabetes are known risk factors for HCC development and so is the presence of liver cirrhosis, which can occur in hepatitis infections, dietary aflatoxins produced by certain moulds, excessive alcohol intake, tobacco smoking, and metabolic associated fatty liver disease. Emerging evidence recognises diet as a potential lifestyle-related risk factor in the development of HCC. This systematic review sought to determine whether there is an association between diet and the development of HCC by analysing 30 observational studies. Reduced risk in HCC development was seen in people who followed either a Mediterranean, Urban Prudent or Traditional Cantonese dietary pattern diet or ate according to the Alternative Healthy Eating Index-2010. Similarly, the intake of vegetables, whole grains, fish, poultry, coffee, plant-based compounds like isoflavones, macronutrients such as monounsaturated fats and micronutrients including vitamin E, vitamin B9, β-carotene, manganese and potassium were associated with reduced risk. Whereby sugar-sweetened beverages and processed red meat consumption appeared to increase HCC risk. This review found no particular impact concerning the DASH diet, nuts and fruit intake. Further discussed are also some of the potential mechanisms that some dairy products and omega-6 have on cancer and HCC risk. In conclusion, certain dietary patterns and diet components influence the risk of HCC development, thus affirming a dietary role in disease development and prevention. However, the impact on diet in high-risk individuals or those who already have HBV or cirrhosis remains to be studied further.