This paper describes our study on high-resolution measurements of the distribution of the radio frequency (RF) magnetic near field from a coplanar waveguide (CPW) with a size similar to power and ground lines in radio frequency integrated circuit chips using a magnetic force microscope tip and amplitude modulation of the line current. Cantilever resonance frequency modulation of approximately 25 kHz supplies the CPW with current and carrier frequencies up to 0.1 GHz. The CPW has a signal line width of 3 μm and a ground line width of 50 μm. The oscillation amplitudes of the tip with and without a DC magnetic field indicates that the distribution of the RF magnetic near field in the proximity of the CPW can be observed for a carrier frequency up to 0.1 GHz. This result also suggests that this method has potential as a new technique for high-resolution RF field measurements.