Objective Theta is the dominant oscillation of local field potentials (LFPs) recorded in rodent hippocampus during voluntary behaviors as well as rapid-eye-movement (REM) sleep.During theta oscillations, diverse types of hippocampal neurons including pyramidal cells and distinct GABAergic interneurons cooperated in time for theta rhythm generation and information processing.Here we reported a new type of neuron recorded in mouse hippocampal CA1, firing one spike per theta circle during theta and silencing during non-theta period, thus called theta pulsing cell.And in this study we also explore the phase precession of theta pulsing cells during active exploration (AE) and REM.Methods Spike and LFPs signal were recorded in hippocampal CA1 of C57BL/6J mice in vivo by 96-channel Plexon system.Results (1) Theta pulsing cells fired at theta frequency and silent during nontheta period, which was of distinct activity from both pyramidal cells and interneurons reported previously.(2) During AE the firing rhythm of theta pulsing cells is faster than LFP theta, representing a phase precession of 273.03 degree, which is comparable with that of hippocampal place cell.During REM, theta pulsing cells fired slower than LFP theta rhythm with phase precession 475.30 degree, which was longer than a theta circle.(3) Theta pulsing cells represented spike-field activity-delay with LFP theta.Conclusion The newly reported theta pulsing cells in hippocampal CA1 was less likely to contribute to theta generation but might provide a clock-like reference for phase precession.