The paper reviews mathematical development of Marx's economics before, by, and after Okishio. Marx's economics is based on dialectics, such as quality and quantity etc., and dialectic feature is not peculiar to Marx's economics, as seen from comparison with physics. Marx's economics has mathematical nature in many fields. The value form theory is established on the distinction between assignment and comparison, for instance. Values and production prices of commodities, the fundamental Marxian Theorem (FMT), the transformation problem, depression theory, socialist planning and relationship among men, all those are mathematical topics. Propositions within linear framework are established mainly by Okishio and his followers. Marx's theory in terms of the Leontief model turned out to be fully dependent on Perron-Frobenius (PF) theorem on nonnegative matrices. Okishio's theorem on technical changes is a corollary of PF theorem. Theory of fixed capital is one of greatest merits and contributions of economic theory of Marx and Sraffa. Fixed capital is a materialistic basis of capitalist production, so that movement of capital depends on fixed capital. It has been disclosed that the renewal process of fixed capital is described as a Markov process, that is accompanied with damped oscillation and initial spikes called Ruchti-Lohmann effect. The cycle of resonance is, nonetheless, as long as twice of durability of fixed capital. Some may argue that Marx's economics lacks micro foundation, but it is not a big point at all. Mathematical theory of Marx's economics follows Marx's fundamental idea that competition in the market is a phenomenal form of the internal dynamics of capitalist production system that governs the process. The equilibrium value itself is, if it exists, determined by a system of simultaneous equations that depict rather structural aspects of economies. Marx's economics is of computational nature, and, in this sense, highly critical against neoclassical economics, that suffers from computational difficulties. Criticism against neoclassical economics is one of important tasks for Marxian economics. It is pointed out that neoclassical macro dynamics should suffer from various formal difficulties, and neoclassical theorem based on saddle path fails in explaining cyclical depression, like 2008 world depression. Future development of Marx's economics should also include topics related to revival and renewed models of socialist planned economies, and nonlinearity or complexity of economic phenomena. As for socialist planning, there is a some stock of discussions before 1990. Fundamental problems are still worth pursuing. Meanwhile, Mandelbrot and economic physics present, from large scale data analyses, serious counter examples against neoclassical economics. This type of approach and method should be digested by Marxian economics. A basic stance of Marx's economics is that relationship among men appears in the relationships among commodities, and that the latter is a projection of the former. Hence Marx's economics is of steric nature. On the contrary, most of bourgeois economics does not analyse relationship of men, so that it is planar, and gives us no deeper insight of our economy.