Given globalization, Internet and frequent migration, the number of bilingual and multilingual speakers is growing in today’s world. There is also a good basis for bilingualism in the Republic of Croatia. The second language of speakers in our country is mostly English, which is not surprising given the fact that English is mandatory in the school system from a very early age, and is increasingly appearing in the system of early and preschool education. This is an opportunity to explore the lexical approach and its differences in Croatian and English, which was examined in this study. Thus, the aim of this research was to measure the speed of lexical access in Croatian and English in sequential bilingual speakers and to examine the differences between them in the two languages. The purpose of this paper is to examine the degree of automation of bilingual speakers in a particular language. It was also examined whether languages affect each other and in what way, all with the help of the task of lexical decision and Stroop-like task. The study was conducted on 30 students from one gymnasium, and two variables were measured - reaction time and accuracy. The influence of the effect of lexicality and the effect of language on these variables was analyzed. The results showed that there is a statistically significant effect of lexicality on both variables on the task of lexical decision, while the effect of language has not been proven on either. However, the interaction between language and lexicality was also obtained on the same task, which showed greater automation in the Croatian language. On Stroop-like task, both examined effects proved to be statistically significant on the variable reaction time, while on the variable accuracy neither lexicality nor language had an impact.