The last decade has witnessed notable advancements in operational forecast systems to predict the Madden-Julian Oscillation (MJO) and its impact on tropical cyclones (TCs). However, limited studies have examined the TC-MJO relationship in long-term climate simulations, particularly over the North Atlantic. This study evaluates how well the TC-MJO relationship is captured in 15 realizations from 9 models that participated in HighResMIP. However, our results show that most models struggle to faithfully reproduce the observed Atlantic TC-MJO relationship. The primary obstacle preventing most HighResMIP models from accurately reproducing the observed impacts of the MJO on Atlantic TCs is the mean state bias in TC climatology, especially over the Atlantic main development region (MDR). All models exhibit negative biases in the TC track density over the tropical North Atlantic. Furthermore, the underestimated MDR TC activity can be primarily attributed to weaker-than-observed African easterly wave (AEW) activity between 5° and 10° N. Errors in the diabatic heating profile within the Atlantic ITCZ lead to insufficient potential vorticity production in the lower troposphere and constrain the amplification of AEWs south of ~12° N. In addition to biased TC climatology, most HighResMIP AGCMs face challenges in realistically representing the MJO-filtered variance and consistently underestimate the eastward-propagating power of the MJO. In models characterized by a higher ratio of eastward-to-westward-propagating variance, the simulated MJO demonstrates a stronger capacity to modulate sub-seasonal TC activity. Those with relatively realistic eastward propagation of the MJO also exhibit greater variance in tropical intra-seasonal convection. Stronger contrasts in convective heating between phases 2-3 and phases 6-7 over the North Atlantic drive larger fluctuations in MDR shear and AEW activity over the Gulf of Mexico and Caribbean Sea, resulting in a more pronounced TC response to the MJO. Overall, our recent work suggests an urgent need for continuous efforts to improve climatological TC activity and the eastward propagation of the MJO in HighResMIP models. These improvements are essential for the models to satisfactorily capture the observed modulations of Atlantic TCs by the MJO.