The mirid bug, Pachypeltis maesarum Kirkaldy, is a new pest on tea where biological and population parameters of this bug are reported, based on field and laboratory experiments. Camellia sinensis was used as host plant and all experiments were carried out at 25 ± 1°C and 12L: 12D. The developmental time for eggs and the total duration of nymphal instars was 8.0 ± 0.32 and 11.5 ± 0.65 days, respectively. Adult females lived longer than males. The intrinsic rate of increase was 0.1081. Mean total leaf consumption by fifth instars was significantly higher than fourth, third, second and first instars. Fifth instars and adult males and females made higher number of punctures per leaf in a day. Males exhibited brownish yellow and dark brownish colour variants while females were brownish yellow. Occurrence of P. maesarum on tea was high during October-November and negligible during January. The alternate host plants recorded for this pest were Acalypha wilkesiana, Psidium guajava and Malvaviscus penduliflorus. Based on the present study it could be forecasted that under favourable conditions P. maesarum can multiply rapidly on tea and establish as a major pest.