The purpose of this study is to identify the authority of the employer to amend the unlimited-period employment contract through answering the following questions: 1. What are the significant difference between the fundamental amendment and the normal amendment? 2- What are the bases on which any employer depends on regarding the fundamental amendment and the non-fundamental one done on the employment contract? 3- What are the conditions and regulations with which any employer should comply in doing the amendment whether it is fundamental or non fundamental? 4. What are the most forms of employment contract amendment? 5- What are the outcomes of employment contract amendment? To answer the aforesaid questions, I divided this study into a prelude and three sections. In the prelude, I approached the difference between fundamental and the non-fundamental amendments performed on the employment contract. In the first section, I approached the bases and conditions of amending the employment contract by the employer. In the second section, I approached the forms of employment contract amendments. In the last chapter, I approached the repercussions of employment contract amendment. The following are the most remarkable findings of this study: 1- To compromise between the rules, "Contract is binding to both parties" and the right granted to any employer in amending the employment contract according to specific conditions and terms. 2- The most important criteria which we could differentiate between the fundamental and non-fundamental amendment are agreement, subjective and the personal criteria the last of which is preferred by the researcher. 3- Any employer should comply with some conditions when amending the employment contract whether this amendment was fundamental or non fundamental. 4- The most important forms of employment contract amendment are as follows: amending the type and amount of work, amending the place and time of work and amendment of the worker's wages. 5- In case any employer executes any amendment on the employment contract, there will be a number of outcomes which differ according to the response of the worker to this amendment.