Background: A renal allograft is the optimum therapeutic option for patients with end stage renal diseases. Nevertheless, rejection still represents a large challenge. So as to overcome this matter, treatment strategies comprise the combined use of anti-inflammatory  and immunosuppressive agents, although they are not free from complications . Interestingly, the major cause of morbidity and mortality after the first transplanted year are due to disorders unrelated directly to immunologic etiology or disease related to immunosuppressive drugs. Objectives: The purpose of this study is to determine the side effects in renal transplant Yemeni patients adherence to cyclosporine compared to tacrolimus sharing the same adjuvant agents which are mycophenolate mofetil "MMF" and prednisone. Subject and methods: This prospective study was carried on 100 kidney transplanted Yemeni patients divided into two groups: cyclosporine group (n=50) and tacrolimus group (n=50), each member of these groups was visited three times, blood samples were collected for biochemical functions including fasting blood sugar, liver enzymes, kidney functions, lipid profiles and white blood cells counts and results were obtained from the tests performed. Body weight and blood pressure had been examined; clinical complications were also recorded. Results: This study showed that serum total and direct bilirubine, gamma glutamyl transferase "GGT" and lipid profiles were elevated in cyclosporine group, whereas in tacrolimus group they were within normal range. The incidence of complicated events reported as follows: Hairtusim, gum hyperplasia, herpeszoster, CUSHING face and obesity were obviously present in cyclosporine group, while in tacrolimus group diabetes mellitus, hair loss and gastrointestinal tract infections were in existence. Conclusion: This study found that a tacrolimus-based treatment was significantly better than an immunosuppressive regimen based on cyclosporine due to the generally less side effects associated with tacrolimus, despite its effect on increasing diabetes among kidney transplant patients. Peer Review History: Received: 18 September 2020; Revised: 5 October; Accepted: 16 October, Available online: 15 November 2020 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, amaka_mgbahurike@yahoo.com Dr. Mohamed Awad AbdAlaziz Mousnad, International University of Africa (IUA) and Sudan, m_abdalaziz@yahoo.com Maged Almezgagi, The Key Laboratory of high-altitude medical application of Qinghai Province, Qinghai Xining 810001, China. 1902244017@qq.com Ali Awad Allah Ali Moh. Saeed, National University, Sudan, alimhsd@gmail.com Comments of reviewer(s): Similar Articles: LEVEL OF LEAD IN THE BLOOD AMONG FUEL STATION EMPLOYEES AND ITS RELATIONSHIP TO IMPAIRED LIVER AND KIDNEY FUNCTIONS IN DAMASCUS; SYRIA: OCCUPATIONAL EXPOSURE TO LEAD BACTERIAL CONTAMINATION OF DIALYSIS WATER AND DIALYSATE AT MUKALLA ARTIFICIAL KIDNEY CENTER IN MUKALLA CITY - HADHRAMAUT - YEMEN: RATE OF CONTAMINATION AND SENSITIVITY OF BACTERIAL ISOLATES TO ANTIBIOTICS