United Microelectronics (UMC) reported Q1 earnings Wednesday of $0.09 per American depositary share, down from $0.13 a year earlier.
Analysts polled by FactSet expected $0.11.
Operating revenue for the quarter ended March 31 was 57.86 billion New Taiwan dollars ($1.78 billion), compared with NT$54.63 billion a year earlier.
An analyst polled by FactSet expected NT$56.97 billion.
The company's shares were up 6% in recent premarket activity.