He was born in 1958 at the station Kzyl-jar of Zhana-Arka district in Karaganda region in a large family (14 children). Mother is the owner of "Altyn Alka" and the title of "Mother heroine". Father was a participant of the great Patriotic War.
He has three children, 10 grandchildren.
After graduating Dzhezkazgan construction College in 1976. He had been sent to the all-Union shock-work Komsomol construction in the village Zhairem. He worked as a bricklayer in PMK vertical trust "Kazmedstroi". In 1978, after demobilization from the Soviet Army, he worked as a fitter, job foreman, foremaster, chief engineer of the capital construction Department, the Supervisor of Contracting Department in Zhairem mining and processing Plant (ZhMВP). Subsequently work activity of G. M. Mukashev is associated with public service and community work.
He worked as the editor in a large-aditions newspaper "Lights of Zhairem".
From 1994 to 1996 he was a Deputy of Karazhal city Maslikhat-Assembly of deputies of Zhezkazgan region.
With the creation of Zhairem-Atasu free economic zone (FEZ) he became the Chairman of the Committee for state property and privatization, Deputy Chairman of the administrative Council of FEZ.
He worked as Deputy Director of the Agency for reorganization and liquidation of enterprises of Karaganda region of the Ministry of Finance of the KR, head of the Department of operational management of the akim of Karaganda, Deputy akim of the Oktyabrsky district of Karaganda city, akim of Karazhal city, Chairman of the city branch of the party "Nur Otan", Deputy head of the Department of Finance, head of the Department of state assets and procurement of Karaganda region. He also worked in the NGO "Republican party" Nur Otan " Deputy Chairman of the Karaganda regional branch of the party "Nur Otan".
In 2003, G. M. Mukashev was elected Deputy Chairman of the Union of writers of Karaganda region.
He has 4 higher education: constructional, financial, economic and legalistic.
In 2013 he defended his thesis on "Management of state assets". Master of economic Sciences.
Academician of the International Informatization Academy (MSIA).
The author of 2 scientific publications on the management of municipal assets, a monograph on the processing of municipal solid waste, 31 rationalization proposals on construction and engineering support, numerous publications in the national and regional press. He is the author of 10 books. Among them artistic-documentary books "Karaganda", "Karazhal-Zhairem aimagy. Karazhal-Zhairem region", "the Story of one family", "How to maintain health and overcome old age", "Mauel Bayterek. Tree of life", poetry books "Love land", " Listen to your heart...", poems and songs about Karaganda "to You, beloved city", reference book "Honorary citizens of Karaganda", scientific book (monograph) "Scientific, technical and economic justification for the construction of a plant for sorting and processing of solid waste".
For his years of work were awarded commemorative medals " 20 years of independence of the Republic of Kazakhstan" (2011), "20 years maslikhats of the Republic of Kazakhstan (2014), all chest marks "Winner of socialist competition" (1977, 1979), sign of II degree "Kaysar» (2010), Honorary certificate from the akim of Karaganda region.
He is marked by the letter of Gratitude of the President of the Republic of Kazakhstan N. A. Nazarbayev (2001) and Gratitude of the President of the Republic of Kazakhstan (2015).