Mycoprotein is a fungal-based ingredient rich in fibre and protein used in meat substitutes called Quorn. Fibre and protein positively regulate glycaemia, lipidaemia and energy intake which are non-communicable diseases' (NCD) markers. We performed a cross-sectional study to investigate the association of mycoprotein intake with diet quality, nutrient, energy intake and NCD risk within 5507 UK free-living adults from the National Diet and Nutrition Survey from years 2008/2009 to 2016/2017. Dietary approaches to stop hypertension (DASH) and healthy diet index (HDI) were calculated to estimate diet quality. Comparison between mycoprotein consumers (>1 % kcal) and non-consumers, and associations between consumers and nutrient intakes, NCD's risk markers and diet quality were investigated using a survey-adjusted general linear model adjusted for sex, age, BMI, ethnicity, socio-economic, smoking status, region of residency, total energy, energy density, HDI and non-mycoprotein fibre intake. Mycoprotein consumers (3·44 % of the cohort) had a higher intake of dietary fibre (+22·18 %, P < 0·001), DASH score (+23·33 %) and HDI (+8·89 %) (P < 0·001, both) and lower BMI (−4·77 %, P = 0·00) v. non-consumers. There was an association (P = 0·00) between mycoprotein consumers and diet quality scores (+0·19 and +0·26), high fibre (+3·17 g), total and food energy (+3·09 and +0·22 kcal), but low energy density intakes (−0·08 kcal/g, P = 0·04). Consumers were negatively associated with fasting blood glucose (−0·31 mmol/l, P = 0·00) and glycated HbA1c (−0·15 %, P = 0·01). In conclusion, mycoprotein intake is associated with lower glycaemic markers and energy density intake, and high fibre, energy intake and diet quality scores. [ABSTRACT FROM AUTHOR]