An increasing number of patients are receiving long-term cardiac monitoring to detect and manage atrial fibrillation (AF). The Reveal LINQ insertable cardiac monitor (ICM) (Medtronic, Minneapolis, MN, U.S.A.), is a miniaturized, leadless, subcutaneous, long-term cardiac monitoring that is widely used to manage arrhythmias. To study the inaccurate (false-positive (FP)) detection of AF during remote cardiac monitoring with the Reveal LINQ ICM. In this non-randomized retrospective study, all clinic patients with a Reveal LINQ ICM implanted between March 2014 and January 2021 were included. The record of the last reported AF for each patient was reviewed. Of 294 consecutive patients, 127 patients (average age= 67.8, Female = 52 (40.9%)) had at least one report of AF. The main reason for implanting cardiac monitoring was AF management (38.6%). There were 34 true AF and 93 inappropriate AF detections. The percentage of FP-reported AF was 73.2%. There was not a significant association between the rate of FP and reasons for cardiac monitoring (P-value = 0.516 by Fisher's exact test). Our findings based on the reason for monitoring are summarized in Table 1. The true diagnosis of reported inappropriate AF were: premature atrial contractions (44.9%) , premature ventricular contractions (11.8%), atrial flutter ( 10.2%) , atrial tachycardia ( 0.8%), premature atrial contractions / ventricular tachycardia (0.8%), noise (4.7%). There is a high rate of inappropriate AF detection by the Reveal LINQ ICM, requiring reviewing the tracing by an expert. More robust algorithms need to be developed for the Reveal LINQ ICM to reduce the rate of FP.