This paper discussed about the development of electronically controlled fertilizer applicator machine based on modified riding type paddy transplanter tractor. The machine had ability to perform variable rate of application dose using urea, phosphor, and NPK compound. The developed variable rate applicator (VRA) equipped with digital controlled metering devices so that the dose of application can be given accurately and the amount of application can be change in flexible way according to recommended dose. The machine has 4 unit of metering devices, has 8 application rows, and equipped with pneumatic diffusers. RTK-DGPS was used to monitor the position in the field. Performance test has been done for several parameters, included uniformity of air flow at each diffuser, granular fertilizer spreader pattern, and linearity of actual amount of fertilizer with respect to the commanded dose. Average rate of air flow in each diffuser was 0.0073 m3/s, with 7.23 % CV. Total working width of the machine was about 5 m. Field capacity was about 0.12 ha/hours. The results of the tests on metering dose showed that the develop VRA could spread fertilizer uniformly and gave accurate application dose. The yield result showed that uniformity of unhulled rice production was reached 74.7%.