Theory of emotional intelligence has been proven to contribute to the teaching and learning process and increase students’ achievement. Goleman stated that smart students do not depend on only the cognitive intelligence called intellectual quotient, but also depend on how they can control and manage their emotions, because IQ only contributes 20% to the factor that determine life success and the rest 80% is something else. This research aimed at investigating how the students’ emotional intelligence was, how the students’ achievement in reading comprehension was and there was or no significant correlation between emotional intelligence and achievement in reading comprehension of tenth grade science students of SMA NU 01 Penawaja Tegal. This study was conducted at SMA NU 01 Penawaja Tegal. Thirty nine of all of tenth science students participated in this study. In the process of collecting data, there were two primary instruments were used. Emotional intelligence scale used to measure the students’ emotional intelligence, while reading test used to know the achievement of students in reading comprehension. Then, there were two secondary instruments were used to verify the validity of the answer of emotional intelligence scale. The result among emotional intelligence scale, observation, and interview were almost same. It means that the differences answers of those three methods were not too far. It is proved that the students’ answer on the scale close to their real condition. The statistical measurement of emotional intelligence showed that students’ emotional intelligence at good category and this result can be accepted to further analysis. In addition, the result of reading test showed that the quality of students’ achievement in reading comprehension were in good category too. It was required from the statistical calculation. Analysis by Pearson Product-Moment Correlation revealed that there was correlation between students’ emotional intelligence and their achievement in reading with r-obtained (0.851). While r-table with 5% significance level was 0.531. Because r-obtained (0.851) was bigger than r-table (0.531), it means that the correlation was significant. At last, if students’ emotional intelligence was high, the achievement in reading would high too. Equally, if students’ emotional intelligence was low, the achievement in reading was low too.