Corona Virus Disease 2019 (COVID-19) is the pandemic world crisis that causes the most dangerous health and economic disaster since the second world war. The world health organization (WHO), in February 2020 has announced about the new epidemic disease caused by 2019-nCoV: 2019 Coronavirus Disease (COVID-19). Several health problems were associated with COVID-19 infection including; dry cough, fever, fatigue, headache, haemoptysis, diarrhoea, dyspnoea, and lymphopenia COVID-19 infection was associated with death especially among older patients. Coronaviruses can infect bone marrow cells leading to abnormal blood production and synthesis (haematopoiesis). Thus, several changes have been reported in haematological parameters among COVID-19 patients. Yet, the mechanisms by which this virus delays and inhibit the hematopoietic system are not clear. This review was aimed to focus on the most common laboratory changes within the haematological parameters including; white blood cells, lymphocytes, platelets and other.