The performance of scientific researchers has been studied from a number of different aspects, mostly in developed countries. This paper attempted to identify salient factors influencing scientific performance at individual level in a developing country. A model describing the productivity and performance of scientific researchers was developed. Four hypotheses were derived from the model; i) the degree of diversity of a researcher will affect the degree of his scientific performance, ii) the degree of dedication will affect the degree of his performance, iii) the degree of research pressure will affect the degree of his performance, and iv) the degree of satisfaction will affect the degree of his performance. Data were collected through questionnaires responded by 48 researchers from two research organizations. The results of data analysis supported the hypotheses in part. Specifically, diversity measured by the number of research areas was related to the productivity of research reports (p<0.05); research pressure influenced the average number of research papers (p<0.05). The results of hypothesis testing of the satisfaction showed mixed directions according to the indicators. Even though the results of data analysis did not support the hypotheses unanimously, probably due to the limitation of sample size, most of the descriptive analysis indicated that the direction of hypotheses in developed countries seemed to be similar in developing country too. However, more research efforts are needed to verify the research findings of developed countries in developing countries.