This study investigated the most common English writing errors committed by students at Al-Istiqlal University. The researchers used a descriptive-analytical approach as it suites the study purposes. The population of the study consisted of all the male and female students at Al-Istiqlal University in Jericho-Palestine. A random sample consisted of 22 students at the modern languages department were chosen to sit for a standardized test to examine the writing errors they may commit in content and organization, mechanism, language use and vocabulary. The written compositions were marked based on content, organization and mechanical accuracy. Results revealed that most of the students were unable to spell correctly, they committed great semantics errors. Moreover, some of them were unable to differentiate between the use of present tense from present continuous tense and they also committed many errors due to sub-verb agreement. Results also indicates that females committed less error than males. Based on the findings it was recommended that intensive writing courses should be added to the program.