The study aimed at investigating the influence of nutrition knowledge and dietary practices on the nutritional status of people living with HIV (PLHIV). In a cross-sectional survey, one hundred and ten adults, comprising 60 females and 50 males infected with HIV were purposively selected and studied using a combination of methods. The study was conducted at the Koforidua Central Hospital in Ghana. The instruments used for data collection included a standardized questionnaire close and open-ended questions, a Food Frequency Questionnaire and a 24-hour-recall dietary assessment method. Weights and heights measurements were used to derive BMIs to assess the nutritional status of the respondents. The Statistical Package for Social Sciences (version 11) and ESHA-FPRO software (version 6.2) were used to analyze the data. The results showed that most of the respondents (91%) had fair to adequate knowledge of nutrition. Ninety-five percent (95%) of the respondents ate three or more times a day and most (85%) of them were not on any special diet. The diet quality of most (91.8%) respondents was rated fair to poor, with 50% having poor diets. The diets of the respondents were generally low in calories and folate. Two-thirds of the respondents had normal BMIs. A negative correlation, although not statistically significant, existed between nutrition knowledge and diet quality. There was also a positive correlation between nutrition knowledge and nutritional status. A significant negative correlation was observed between the quality of diets of respondents and their nutritional status. Based on the findings, it was concluded that nutrition knowledge did not influence the quality of respondents’ diets to a large extent but diet quality determined nutritional status.