Adequate protein intake is essential for maintaining muscle and bone health (1). In the context of an ageing population, it is not only the amount of protein that matters, but also its source and quality, which are increasingly recognised as factors in preserving musculoskeletal function. With the growing shift towards a more plant-based diet, driven largely by sustainability concerns, understanding protein source intake and quality becomes even more crucial (2). However, despite growing awareness of protein’s importance, there is a lack of evidence for the current protein intake, source intake and quality in the Australian population. The aim of this study was to assess protein intake, source and quality in a nationally representative sample of Australian older adults. This study is a cross-sectional secondary data analysis including n = 2819 participants aged 55 years and over from the Australian National Nutrition and Physical Activity Survey (S), part of the 2011–13 Australian Health Survey (AHS). Dietary data (two 24-hour recalls) were used to derive total protein intake (g/day and g/kg/day) as well as protein intake from either animal or plant-based protein sources (g/day and percentage of total protein intake). Protein quality per meal was derived using the alpha tool (3), and expressed as a meal protein quality score ranging from 0-100, with a score of 100 being the highest protein quality. Of the n = 2819 participants (mean age 67 ± 9), n = 1520 were female, and n = 1299 were male. The daily protein intake was 83.7 g/day, with 64.4% from animal-based protein sources and 35.7% from plant-based protein sources. Breakfast had the highest proportion of plant-based protein sources (55.4%), followed by lunch (32.3%) and dinner (21.6%). In contrast, animal-based protein sources were highest at dinner (78.4%), followed by lunch (67.7%) and breakfast (24.5%). Protein quality scores (daily and per meal) will be assessed. The study will provide insight into the older Australians' daily protein intake, source intake and distribution as well as protein quality. This is essential for effectively identifying nutritional strategies to manage age-related diseases such as sarcopenia and osteoporosis, and as such, support healthy ageing.