An electrical equivalent circuit model of InGaAs/InP uni-travelling carrier photodiode (UTC-PD) is presented. The model is suitable to be built on any electrical circuit simulator to optimize the design parameters of the device. Its performance in terms of bandwidth, linearity, third order inter-modulation distortion and output photo current are investigated. Simulation techniques to measure inter-modulation distortion products and linearity are given in detail. The result obtained by the modeling technique is validated through a comparison with the reported experimental results. It is shown that 3 dB cutoff frequency and output photocurrent can be substantially improved by inserting a small inductance in series with the load together with choosing an optimum absorption layer width in UTC-PD. This technique does not sacrifice the device linearity to a large extent. © 2014, Springer Science+Business Media New York.