From 1885 onward he continued his studies at the Rijksakademie voor beeldende kunsten (State Academy of fine arts).
[1] In this period he met other artists as Ferdinand Hart Nibbrig, Richard Roland Holst and Isaac Israëls.
He lived and worked in various places in the province Drenthe, in Rotterdam, in The Hague, in De Steeg near Arnhem, where he shared a studio with the painter Edzard Koning and in Renkum.
During the period of his artistic search Simon Moulijn followed the examples set by the modern French painters as well as Jan Toorop and Vincent van Gogh.
He worked amongst other places in the Dutch provinces Drenthe, North Brabant, Gelderland (Guelders), Zeeland and in the southern part of Limburg.
Apart from his first paintings in academic style his independent development began with the simplifying nearly abstract sceneries influenced by symbolism and a certain mysticism.
The main part in his stone drawings is played by peaceful rivers, woods, parks, but also fortresses and lively, urban landscapes of the harbour of his native town Rotterdam.
[10] Moulijn's use of lithography also influenced his way of painting and the execution of works in these fully different techniques gave him a special position in the Dutch art scene of the first half of the twentieth century.
Moulijn also created drafts for book covers, drawings, etchings, wood engravings and commercial art.
In 1934 Moulijn earned special merits for his part in the organisation of an Exhibition of Dutch fine arts in Budapest.