Electricity supply in Nigeria is epileptic and characterized by extensive outages. The new NIPP plants constructed have not improved the power situation in the country. The performance of Alaoji Thermal Power Station being one of the new NIPP plants with an installed capacity of 504.4MW (consisting of 4 X 126.1MW GE frame-9EA gas turbines) was studied. The study evaluated the performance of the plant for the period of January to December, 2016. The key performance indices involved were CF, PUF, LF, and AF. The required data for the analysis were obtained from the plant's operational records and personal interview of the relevant staff. The results of the study are shown in Table 1 – 2 and figures 1 – 7 for running hours, energy generated, load factor, availability factor, shortfall in energy generation and plant use factor respectively. When the obtained values were weighed against the International best practice of 80% (LF), 50 - 70% (PUF) and 95% (AF). Shortfall in energy generation ranged from 1.4% to 90.5%, this is in excess of 5 – 10% average acceptable value. The Average PUF was 20.1%, indicating that the plant was grossly underutilized during the study period. The plant had a capacity factor ranging from 7.1 - 37.5% with an average CF of 20% for the review period. It was evident from the results that the plant performed poorly during the period under review. This was attributed to grid restrictions, insufficient gas supply and unavailability of spare parts for maintenance. It is suggested that the management should address the challenges so as to enhance the performance of the plant.