This report describes a simple design of noninvasive carbon tube electrodes that facilitates electrocardiography (ECG) in mice during cardiac multimodality preclinical imaging. Both forepaws and the left hindpaw, covered by conductive gel, of mice were placed into the openings of small carbon tubes. Cardiac ECG-gated single-photon emission CT, X-ray CT, and MRI were tested (n = 60) in 20 mice. For all applications, electrodes were used in a warmed multimodality imaging cell. A heart rate of 563 ± 48 bpm was recorded from anesthetized mice regardless of the imaging technique used, with acquisition times ranging from 1 to 2 h.