In WebQuest online learning Strategies, students are given the opportunity to search using the selected websites. Teacher usually plays a role of facilitator and allows the students to decide the pace of learning by giving them chance to exhibit their talents unlike in traditional online learning where students are free to search for information using any available website.The major concern of this study has to do with poor writing skills of senior secondary school students. Therefore, this study explored theeffects of WebQuest Online learning strategies on the written English of students of senior secondary schools in Kaduna State.Five research questions and five hypotheses were generated, tested and answered. Quasi-experimental research design was adopted for the study. The population of the study comprised all the 2015/2016 registered SSII students of the seven (7) public seniorsecondary schools with ICT facilities in Giwa Zone. The schools registered one thousand six hundred and sixty (1660) students with two hundred and forty two (242) computers and online facilities. One hundred and twenty students were selected from SS11 students of Yusuf AbokiSenior Secondary School, Shika, Government Senior Secondary School, Hunkuyi, Government Senior Secondary School, Bomo and Government Senior Secondary School, Kudan with one hundred and thirty two (132) computers. Essay question was used as the instrument for data collection. Essay questions were used as the instrument for data collection.The investigation involved pre-test, test I, test II, test III and final test. After the pre-test, the students were exposed to the treatment and test I was given, followed by another treatment and test II, test III and final test for narrative, descriptive and expository essay.T-test was used for the test with the aim of identifying the differences between the performance of students exposed to WebQuest online learning strategies and those that were not exposed to the treatment.The overall study results revealed significant differences between the written English mean performance score of the experimental and control groups.The study proved thatuse ofWebQuestonline learning strategies in language learning led to greater writing achievement of the students.The results also showed that the treatment was effective for both male and female students. The study, therefore, recommends that students should be given the opportunity to exercise their abilities and be exposed to WebQuest online learning strategies