Introduction Kidney cancer (renal cell cancer [RCC]) is the 7th commonest cancer in the UK. As RCC is largely curable if detected at an early stage and most patients have no symptoms, there is international interest in evaluating a screening programme for RCC. The Yorkshire Kidney Screening Trial (YKST) will assess the feasibility of adding non-contrast abdominal CT scanning to screen for RCC and other abdominal pathology within the Yorkshire Lung Screening Trial (YLST), a randomised trial of community-based CT screening for lung cancer. Methods and analysis In YLST, ever-smokers aged 55–80 years registered with a general practice in Leeds have been randomised to a Lung Health Check assessment, including a thoracic low-dose CT (LDCT) for those at high risk of lung cancer, or routine care. YLST participants randomised to the Lung Health Check arm who attend for the second round of screening at two years without a history of RCC or abdominal CT scan within the previous six months will be invited to take part in YKST. We anticipate inviting 4,700 participants. Those who consent will have an abdominal CT immediately following their YLST thoracic LDCT. A sub-set of participants and the health care workers involved will be invited to take part in a qualitative interview. Primary objectives are to: quantify the uptake of the abdominal CT, assess the acceptability of the combined screening approach and pilot the majority of procedures for a subsequent randomised controlled trial of RCC screening within lung cancer screening. Ethics and Dissemination 4 YKST was approved by the North West-Preston Research Ethics Committee (21/NW/0021), and the Health Research Authority on 3/2/2021. Trial results will be disseminated at clinical meetings, in peer-reviewed journals and to policy makers. Findings will be made available to participants via the study website (www.YKST.org). Trial registration numbers NCT05005195 and ISRCTN18055040